[TYPO3] 3.8.1: help!!!! blank page shown on back end! Problem with graphic libraries?

[seml at symbulos.com]

Dear friends,

3.8.1 here, testsite package. 

Everything ok, but when I try to login in into back end, it 
only shows a white, empty page. Front end shows the package 
normally.

Everything seems OK here! I checked many times, read the 
documentation.

ImageMagick 6.2.4 with LZW capabilities. 
GD 2.0.3 with Freetype 
Apache 2.0.54
PHP 5.0.4

I have tried to reformulate the question so that someone can 
maybe answer.

Help!!!!

seml
 
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