Adobe Illustrator CS5.5 export to PSD not enough memory

******BUG******
Concise problem statement:
Not able to export AI to PSD due to 'Not Enough memory' message.
Steps to reproduce bug:
 1. create a medium complex AI file 45 x 56 cm, 6 layers
 2. export to Photoshop, with layers, 300dpi
 3. See how it not always works
 Results: Error message
 Expected results:
A .psd file.

Remarks: my system has 12gB RAM and >100gB scratch disk. The .AI file is 3.3mB, the resulting .psd should be approx. 300mB. So memory shouldn't be the problem. I think some old code in AI prevents it from making use of all available memory...