Problem with attachments in php 5.3.1

[TechMonster]

My temp server was running 5.2.11 with no problems with adding attachments.  I moved to the new server which was php 5.3.1 and most attachments (weird a .ppt or .xls works but rest does not) will not add to a new email. I tried running the old 5.2.11 php.ini on 5.3.1 engine and it still did not work. My temp solution was to install 5.2.11 engine. Does anyone else have this issue or at least a solution? This is Apache 2.2 and running on windows.

Thanks
Travis

[SKaero]

try adding the file types in the [RC root]/config/mimetypes.php

[TechMonster]

OK that helped. But this brings a few questions. First. Why would I need to define a mime type for sending attachments? Second I couldn't possibility list all the mime types for all my customers. Do you have a general catch all? What changed in php version 5.2.11 to 5.3.1 that doesn't allow this to catch all? In 5.2.11 I can upload my .emodel files but in 5.3.1 I can't without adding this mime type.
Thanks
Travis

[TechMonster]

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