MCD Autconfig failing on getenv

[R Skinner]

Hi guys, this is probably the best list for this query - I'm on most lists here, but I'm not sure I'm specifically on this one so if I could be CC in it would be great.
I have an interesting issue with Thunderbird specifically which I have been banging my head on for about a week on and off with no success. I'm using Thunderbird 17.x from ports and setup autconfig from various blogs, wikis, and docs on the subject. But no matter which way I try I cannot seem to get it to work, it just won't get the username so it borks the URL and the server errors. Getenv function doesn't appear to work at all.
Any ideas on how to fix this? Debug refuses to offer any helpful clues except the error from the server. The server just shows that no username is showing in the URL.
Cheers