What version of the httpmail plugin are you using? (should tell you under the httpmail section of preferences)
I've been using 1.41 with no problems. Latest version is 1.42 which you can get from here:
http://sourceforge.net/projects/httpmail-plugin
If you haven't already, maybe you should try uninstalling httpmail and reinstalling it.
From the FAQ (should have been in the .dmg which has the httpmail plugin)
" How do I get rid of this thing?
1. To de-install the plugin, you must delete the httpmail_panther.mailbundle folder in the Bundles folder of the current user.The path is likely to be: Macintosh HD / Users / [current user name] / Library / Mail / Bundles. You must also delete every http-Mail folder that was created in the Bundles folder.
2. Then you must de-activate the plug-in by executing the following command in a Terminal window, paying great attention to the exact spelling:
defaults write com.apple.mail EnableBundles 0
If you are upgrading from an older version:
1. Make sure Mail is not running
2. Run the installer. This will overwrite the old plugin and replace it with the new one.
Alternatively if you want to do it manually
1. Make sure Mail is not running
2. You must replace the httpmail_panther.mailbundle (or httpmain.mailbundle under Jaguar) plugin with the newer one,. Simply trash the OLD httpmail_panther.mailbundle folder from the Bundles folder of the current user. The path is likely to be: Macintosh HD / Users / [current user name] / Library / Mail / Bundles.
3. Then copy (drag) the NEW httpmail_panther.mailbundle folder from the volume httpmail plugin you just downloaded, to the Bundles folder.
There is no need to modify your existing mailboxes. If your upgrade was successful, the advanced panel of your accounts will reflect the new version number. "
Alternatively, if you don't want to use httpmail or can't get it working, I've got plenty of gmail invites if you would like one (you can set up gmail to use pop so you can check it through mail).
