GVMax has been a bit moody the last few weeks and the problem is probably related to GTalk notifications.
Since a lot of the new users use GVMax to perform an HTTP Post (mainly WM7 users) I decided to split that functionality out into a separate service .
To use it you will need to :
1- Forward your GV emails to email@example.com
2-Log into the service at https://gvmax-post.appspot.com and type in the HTTP Post URL you want to use.
I will probably provide an API for WM7 Phone developers so that they can do step 2 for there users automatically.
As for step 1, you create the gmail filter in the same way you would do in GVMax (if doing it manually (https://www.gvmax.com/filters)), but forward it to firstname.lastname@example.org instead.
This app runs wholly app engine it should be VERY reliable, since it does very little.
And by the way it is open source ( http://code.google.com/p/gvmax-post/ )