When I attach a file using the IMP webmail interface I get an error message back if the file is much bigger than 100KB. Anything less than about 100KB and it doesn't seem to have a problem. I'm just testing SME server at the moment, so I don't have it connected to the internet. I'm just trying to send an e-mail from one mail account on the server to another.
The message reads as follows:
Fatal Error: Maximum execution time of 30 seconds exceeded in /home/httpd/html/horde/lib/horde.lib on line 1126
I hope you can make heads or tails out of it. Let me know if there's an easy fix.