Index: chan_sip.c
===================================================================
--- chan_sip.c	(revision 189266)
+++ chan_sip.c	(working copy)
@@ -2853,6 +2853,24 @@
 			ast_str_append(&req.data, 0, "%s", buf);
 			req.len = req.data->used;
 		}
+		/* i have seen this with a softphone that brodcast every five sec. SIP dummy messages as NAT opener
+		   and the content was just "\r\n" which was bufferd in the buf before and then we get SIP messages with
+		   a extra blank line at the beginning. This blank line then totally confuses the following parser with the
+		   result that no incoming call were possibly. So i just check if the first line is a blank line, and remove it.
+		*/
+		if (strncmp(req.data->str, "\r\n", 2) == 0) {
+			ast_log(LOG_WARNING, "There was a blank line at the top this message and i removed it. Probably this is because your phone sent us brocken SIP dummy packages before\n");
+			/*			
+			int i;
+		   for (i=0 ; req.data->str[i] != '\0' ; i++) {
+		   	req.data->str[i] = req.data->str[i+2];
+		   }
+		   * choose which one is better, the loop or the strstr/strcpy variant
+		   */
+		   strcpy(req.data->str, strstr(req.data->str, "\r\n") + 2 );
+		   req.data->used = req.data->used -2;
+		   req.len = req.data->used;
+		}
 		copy_request(&reqcpy, &req);
 		parse_request(&reqcpy);
 		/* In order to know how much to read, we need the content-length header */