Merged revisions 264114 via svnmerge from

https://origsvn.digium.com/svn/asterisk/trunk

........
  r264114 | dvossel | 2010-05-19 09:38:02 -0500 (Wed, 19 May 2010) | 13 lines
  
  fixes crash during dtmf
  
  During the processing of Cisco dtmf the dtmf samples were
  not being calculated correctly.  In an attempt to determine
  what sample rate was being used, a NULL frame was processed
  which caused a crash.  This patch resolves this.
  
  (closes issue #17248)
  Reported by: falves11
  Patches:
        issue_17248.diff uploaded by dvossel (license 671)
........


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@264115 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/rtp.c

@@ -992,10 +992,10 @@ static struct ast_frame *process_cisco_dtmf(struct ast_rtp *rtp, unsigned char *
 		}
 	} else if ((rtp->resp == resp) && !power) {
 		f = create_dtmf_frame(rtp, AST_FRAME_DTMF_END);
-		f->samples = rtp->dtmfsamples * (rtp_get_rate(f->subclass) / 1000);
+		f->samples = rtp->dtmfsamples * (rtp->lastrxformat ? (rtp_get_rate(rtp->lastrxformat) / 1000) : 8);
 		rtp->resp = 0;
 	} else if (rtp->resp == resp)
-		rtp->dtmfsamples += 20 * (rtp_get_rate(f->subclass) / 1000);
+		rtp->dtmfsamples += 20 * (rtp->lastrxformat ? (rtp_get_rate(rtp->lastrxformat) / 1000) : 8);
 	rtp->dtmf_timeout = dtmftimeout;
 	return f;
 }