diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index 273c782..97b51a7 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -767,7 +767,7 @@
                    "http upstream send request");
 
     if (!u->request_sent && ngx_http_upstream_test_connect(c) != NGX_OK) {
-	ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_ERROR);
+        ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_ERROR);
         return;
     }
 
@@ -914,7 +914,7 @@
     }
 
     if (!u->request_sent && ngx_http_upstream_test_connect(c) != NGX_OK) {
-	ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_ERROR);
+        ngx_http_upstream_next(r, u, NGX_HTTP_UPSTREAM_FT_ERROR);
         return;
     }
 
@@ -1259,33 +1259,33 @@
 #if (NGX_HAVE_KQUEUE)
 
     if (ngx_event_flags & NGX_USE_KQUEUE_EVENT)  {
-	if (c->write->pending_eof) {
-	    (void) ngx_connection_error(c, c->write->kq_errno,
-			            "kevent() reported that connect() failed");
-	    return NGX_ERROR;
-	}
+        if (c->write->pending_eof) {
+            (void) ngx_connection_error(c, c->write->kq_errno,
+                                    "kevent() reported that connect() failed");
+            return NGX_ERROR;
+        }
 
     } else
 #endif
     {
-	err = 0;
-	len = sizeof(int);
+        err = 0;
+        len = sizeof(int);
 
-	/*
-	 * BSDs and Linux return 0 and set a pending error in err
-	 * Solaris returns -1 and sets errno
-	 */
+        /*
+         * BSDs and Linux return 0 and set a pending error in err
+         * Solaris returns -1 and sets errno
+         */
 
-	if (getsockopt(c->fd, SOL_SOCKET, SO_ERROR, (void *) &err, &len)
-	    == -1)
-	{
-	    err = ngx_errno;
-	}
+        if (getsockopt(c->fd, SOL_SOCKET, SO_ERROR, (void *) &err, &len)
+            == -1)
+        {
+            err = ngx_errno;
+        }
 
-	if (err) {
-	    (void) ngx_connection_error(c, err, "connect() failed");
-	    return NGX_ERROR;
-	}
+        if (err) {
+            (void) ngx_connection_error(c, err, "connect() failed");
+            return NGX_ERROR;
+        }
     }
 
     return NGX_OK;
diff --git a/src/mail/ngx_mail_auth_http_module.c b/src/mail/ngx_mail_auth_http_module.c
index febeb55..8028c95 100644
--- a/src/mail/ngx_mail_auth_http_module.c
+++ b/src/mail/ngx_mail_auth_http_module.c
@@ -686,19 +686,19 @@
                     ctx->err.len = ctx->errcode.len + ctx->errmsg.len
                                    + sizeof(" " CRLF) - 1;
 
-		    p = ngx_palloc(s->connection->pool, ctx->err.len);
-		    if (p == NULL) {
-			ngx_close_connection(ctx->peer.connection);
-			ngx_destroy_pool(ctx->pool);
-			ngx_mail_session_internal_server_error(s);
-			return;
-		    }
+                    p = ngx_palloc(s->connection->pool, ctx->err.len);
+                    if (p == NULL) {
+                        ngx_close_connection(ctx->peer.connection);
+                        ngx_destroy_pool(ctx->pool);
+                        ngx_mail_session_internal_server_error(s);
+                        return;
+                    }
 
-		    ctx->err.data = p;
+                    ctx->err.data = p;
 
-		    p = ngx_cpymem(p, ctx->errcode.data, ctx->errcode.len);
+                    p = ngx_cpymem(p, ctx->errcode.data, ctx->errcode.len);
                     *p++ = ' ';
-		    p = ngx_cpymem(p, ctx->errmsg.data, ctx->errmsg.len);
+                    p = ngx_cpymem(p, ctx->errmsg.data, ctx->errmsg.len);
                     *p++ = CR; *p = LF;
                 }
 
diff --git a/src/mail/ngx_mail_handler.c b/src/mail/ngx_mail_handler.c
index 418d144..e419832 100644
--- a/src/mail/ngx_mail_handler.c
+++ b/src/mail/ngx_mail_handler.c
@@ -297,19 +297,19 @@
                      - s->salt.data;
 
         if (s->protocol == NGX_MAIL_POP3_PROTOCOL) {
-	    s->out.data = ngx_palloc(c->pool,
+            s->out.data = ngx_palloc(c->pool,
                                      greetings[0].len + 1 + s->salt.len);
-	    if (s->out.data == NULL) {
-		ngx_mail_session_internal_server_error(s);
-		return;
-	    }
+            if (s->out.data == NULL) {
+                ngx_mail_session_internal_server_error(s);
+                return;
+            }
 
-	    p = ngx_cpymem(s->out.data,
+            p = ngx_cpymem(s->out.data,
                            greetings[0].data, greetings[0].len - 2);
-	    *p++ = ' ';
-	    p = ngx_cpymem(p, s->salt.data, s->salt.len);
+            *p++ = ' ';
+            p = ngx_cpymem(p, s->salt.data, s->salt.len);
 
-	    s->out.len = p - s->out.data;
+            s->out.len = p - s->out.data;
         }
     }
 
@@ -1408,31 +1408,31 @@
             case NGX_SMTP_MAIL:
 
                 if (s->connection->log->log_level >= NGX_LOG_INFO) {
-		    l.len = s->buffer->last - s->buffer->start;
-		    l.data = s->buffer->start;
+                    l.len = s->buffer->last - s->buffer->start;
+                    l.data = s->buffer->start;
 
-		    for (i = 0; i < l.len; i++) {
-			ch = l.data[i];
+                    for (i = 0; i < l.len; i++) {
+                        ch = l.data[i];
 
-			if (ch != CR && ch != LF) {
-			    continue;
-			}
+                        if (ch != CR && ch != LF) {
+                            continue;
+                        }
 
-			l.data[i] = ' ';
-		    }
+                        l.data[i] = ' ';
+                    }
 
-		    while (i) {
-			if (l.data[i - 1] != ' ') {
-			    break;
-			}
+                    while (i) {
+                        if (l.data[i - 1] != ' ') {
+                            break;
+                        }
 
-			i--;
-		    }
+                        i--;
+                    }
 
-		    l.len = i;
+                    l.len = i;
 
-		    ngx_log_error(NGX_LOG_INFO, s->connection->log, 0,
-				  "client was rejected: \"%V\"", &l);
+                    ngx_log_error(NGX_LOG_INFO, s->connection->log, 0,
+                                  "client was rejected: \"%V\"", &l);
                 }
 
                 text = smtp_auth_required;
diff --git a/src/mail/ngx_mail_proxy_module.c b/src/mail/ngx_mail_proxy_module.c
index 03f21eb..894c01d 100644
--- a/src/mail/ngx_mail_proxy_module.c
+++ b/src/mail/ngx_mail_proxy_module.c
@@ -702,20 +702,20 @@
 
         case ngx_smtp_helo:
         case ngx_smtp_noxclient:
-	    if (p[0] == '2' && p[1] == '5' && p[2] == '0') {
-		return NGX_OK;
-	    }
-	    break;
+            if (p[0] == '2' && p[1] == '5' && p[2] == '0') {
+                return NGX_OK;
+            }
+            break;
 
         case ngx_smtp_start:
         case ngx_smtp_xclient:
-	    if (p[0] == '2' && p[1] == '2' && p[2] == '0') {
-		return NGX_OK;
-	    }
-	    break;
+            if (p[0] == '2' && p[1] == '2' && p[2] == '0') {
+                return NGX_OK;
+            }
+            break;
         }
 
-	break;
+        break;
     }
 
     pcf = ngx_mail_get_module_srv_conf(s, ngx_mail_proxy_module);