[TYPO3-windows] 4.5.7 upgrade broke display thumbnails

[Claus Fassing]

Hello,

after upgrade from 4.2.x to 4.5.7 we don't get display the thumbnails 
anymore. Generation of the thumbnails in typo3temp is working fine, but 
couldn't fetched through thumbs.php
All image processing tests from install tool passed successfully.
There is only a warning
Warning: Mismatch between the version of ImageMagick () and the 
configuration of [GFX][im_version_5] (im6)
But doesn't matter what we set as im_version_5, the warning is still 
displayed.
Looks more like the system is not able to fetch the IM version.

We don't use realurl !

IIS 6.0
imagemagick-6.3.5-q16
PHP 5.2.3

Do we may use a wrong combinations of GFX options ?

$TYPO3_CONF_VARS['GFX']['im'] = '1';
$TYPO3_CONF_VARS['GFX']['im_path'] = 'd:\\imagemagick-6.3.5-q16\\';
$TYPO3_CONF_VARS['GFX']['im_path_lzw'] = 'd:\\imagemagick-6.3.5-q16\\';
$TYPO3_CONF_VARS['GFX']['im_version_5'] = 'im6';
$TYPO3_CONF_VARS['GFX']['TTFdpi'] = '96';
$TYPO3_CONF_VARS['GFX']['gdlib_2'] = '1';
$TYPO3_CONF_VARS['GFX']['jpg_quality'] = '90';
$TYPO3_CONF_VARS['GFX']['im_imvMaskState'] = '1';
$TYPO3_CONF_VARS['GFX']['im_negate_mask'] = '1';
$TYPO3_CONF_VARS['GFX']['im_v5effects'] = '1';
$TYPO3_CONF_VARS['GFX']['im_useStripProfileByDefault'] = '0';
$TYPO3_CONF_VARS['GFX']['im_stripProfileCommand'] = '';
$TYPO3_CONF_VARS['GFX']['thumbnails_png'] = '1';
$TYPO3_CONF_VARS['GFX']['gif_compress'] = '0';
$TYPO3_CONF_VARS['GFX']['gdlib_png'] = '1';
$TYPO3_CONF_VARS['GFX']['im_noFramePrepended'] = '1';
$TYPO3_CONF_VARS['GFX']['im_mask_temp_ext_noloss'] = 'png';
$TYPO3_CONF_VARS['GFX']['im_combine_filename'] = 'composite';
$TYPO3_CONF_VARS['GFX']['png_truecolor'] = '1';
$TYPO3_CONF_VARS['GFX']['im_noScaleUp'] = '1';

Regards Claus