In reference to the fix made for 13871, I was

In reference to the fix made for 13871, I was
merging the fix into 1.6.0 and realized I missed
the code in the h-exten block, and didn't catch it
because my test case had the h-exten commented out.

So, this corrects the code I missed, as a
preventative against another crash report.
Tested with the h-exten defined, all is well.

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@158603 65c4cc65-6c06-0410-ace0-fbb531ad65f3