[Typo3] Enable <hx> in fdfx_2cols/fdfx_3cols

[Uwe Brechlin]

I have the extensions fdfx_2cols/fdfx_3cols installed and enabled. They 
work fine except for that I cannot use headers such has <h1>, <h2>, etc. 
in the boxes. They are obviously not parsed correctly and shown 
literally as <H2 class="">My header text...</H2>.

Does anybody know how to enable headers in fdfx_2cols/fdfx_3cols?

Best regards,
Uwe Brechlin