BadStatusLine when downloading attachments


We have users who are receiving this on their mobile devices "GroupWise attachment error" as an email. (that is all it says in the body of the email)

We use GroupWise 2012, latest and greatest. Mobility server 1.24. And the mobiles are iPhone 5's.

In the default.pipeline1.groupwise-AppInterface.log I see the following errors:

2013-06-28 13:39:11.387 ERROR [ATT_POOL_Thread-9] [gwconnectorlogic:1464] [userID:******] [eventID:] [objectID:] [AttachmentsDownload] An unexpected error -BadStatusLine- occurred while downloading attachment TEXT.htm

It doesn't seem to be that the attachment is too big, because I have different errors for that.
If I google for BadStatusLine it appears it is a Python issue...
Any ideas how to troubleshoot?