Parallels 4 does not start

After upgrading from 3 to 4, the Parallels Desktop application quits without warning. Auxiliary applications (Explorer, Image Tool…) display a message "Unable to find Parallels SDK library" and also quit.

Explanation: my /usr/local directory is located on a secondary volume through a symlink:

/usr/local -> /Volumes/Applications/usr/local

The Parallels installer puts in /usr/local/lib a link to a library located on the startup volume with a relative link:

libprl_sdk.3.0.0.dylib -> ../../../Library/Parallels/Parallels Service.app/Contents/Frameworks/Parall...

In my configuration, this fails and I had to replace this with an absolute link:

libprl_sdk.3.0.0.dylib -> /Library/Parallels/Parallels Service.app/Contents/Frameworks/Parall...

Then everything is back to normal. I had then a number of difficulties to convert my machines, which might be solved with the last version. But the stupid licensing policy prevents me to switch to the English version while the French version is still not updated !