[TYPO3] sr_feuser_register doesn't send htmlemail

[aowen at swissonline.ch]

Hi

I have a problem with HTML-Email. The module only sends in plaintext
even though i've got "enableHTMLMail = 1" in my template under constants
as you can see in the attachement.

i'm using Typo3 4.04, sr_feuser_register 2.5.5, direct_mail
2.2.0 and static_info_tables 2.0.2.

what can i do, where shall i start to look?