PGP not decrypting

[gerritb]

Hi,
I have just installed a fresh OTRS3.1.11 on a equally fresh Ubuntu 12.04.1 w/ apache2, mysql and perl. Everything is working like a charm, except decryption of e-mail using GPG.
GPG is also properly installed and if I cut and paste the crypted content into a text file and decrypt it on the host system, decryption works fine. There is no indication of decryption attempts (or failures) in the article header so I started analysing the way OTRS decrypts messages.

By adding log statements at various places in Kernel/Output/HTML/ArticleCheckPGP.pm I was able to find out that the article body appears to be in latin1 but parsed as UTF-8. The first RE in ArticleCheckPGP.pm "/[\s\n]*^----- BEGIN PGP MESSAGE -----/m" fails for that reason, because the whitespaces in front of my message are apparenlty not \r\n. If I remove the '^' it attempts to decrypt the message but then fails, because the article is stored in tmp as a latin1 encoded file ( tested by also dumping the content into a file which does not get removed) , which GPG apparently cannot parse (errors: eof, no PGP data).

I couldn't find any other reports of similar issues, so I figure I must be doing something wrong here since everyone else can operate PGP via OTRS.
I have checked all charset encodings on the host and they are all UTF-8. (mySQL character_set_server was 'latin1' and changed to 'utf-8'. "support" reports all green items on character sets.

OTRS fetches e-mail from Exchange 2012 via POP3 beautifully. We're using PGP Desktop 10 for our e-mail encryption (so no GPG4WIN in exchange, or Thunderbird with GPG.) I think I need to configure something to make sure OTRS converts these e-mails in UTF8 before processing them any further, or in that direction.

So does anyone have clues on how to solve this problem?

Thank you!