Mime Mail in Drupal 6, "Parse error: syntax error"

I recently installed the SimpleNews module into my Drupal 6 site. In order to send HTML mail, Mime Mail is required. I installed the Mime Mail 6.x-1.x-dev module (The only one for D6). And I get the error:

Parse error: syntax error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /home/xxx/public_html/drupal/sites/all/modules/mimemail/mimemail_css_combiner.module on line 5

Anyone had this problem and solved the problem?

Thanks
Tom