Backport fix for #6229, hangup on polarity reversal

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.2@8573 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_zap.c

@@ -4200,6 +4200,10 @@ static struct ast_frame *zt_handle_event(struct ast_channel *ast)
                                      (ast->_state == AST_STATE_RINGING))) {
                                         ast_log(LOG_DEBUG, "Answering on polarity switch!\n");
                                         ast_setstate(p->owner, AST_STATE_UP);
+					if(p->hanguponpolarityswitch) {
+						gettimeofday(&p->polaritydelaytv, NULL);
+					}
+					break;
                                 } else
                                         ast_log(LOG_DEBUG, "Ignore switch to REVERSED Polarity on channel %d, state %d\n", p->channel, ast->_state);
 			}