[Typo3] PNG troubles

[Artem Matevosyan]

Hello

Here are the errors:

Warning: imagecreatefrompng(): 'typo3temp/pics/45618d1335.png' is not a valid PNG file in /path/t3lib/class.t3lib_stdgraphic.php on line 2636
Warning: imagesx(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 409
Warning: imagesy(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 410
Warning: imagedestroy(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 394
Warning: imagecreatefrompng(): 'typo3temp/pics/67209d8e8b.png' is not a valid PNG file in /path/t3lib/class.t3lib_stdgraphic.php on line 2636
Warning: imagesx(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 409
Warning: imagesy(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 410
Warning: imagedestroy(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 394
Warning: imagecreatefrompng(): 'typo3temp/pics/8a8c3647df.png' is not a valid PNG file in /path/t3lib/class.t3lib_stdgraphic.php on line 2636
Warning: imagesx(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 409
Warning: imagesy(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 410
Warning: imagedestroy(): supplied argument is not a valid Image resource in /path/t3lib/class.t3lib_stdgraphic.php on line 394

Caused by GMENU trying to generate PNG icons for menu by imagemagick
6.2. Source icons saved as GIF. Typo regenerates them using PNG
format. The result is: empty pictures and errors listed above or just
empty pictures took from cache and no errors.

Does anyone know what to do?

Cross-posted to russian mail-list.