I contacted the guy. Here is what he answered:
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« Sent to: vakkov on: Today at 22:21 »
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Quote from: vakkov on Today at 22:17
Hello dj U.G.
Can you please give me a link to the source code so i can see if it's not the same i have?
Cheers



Symbian OS layer:

http://www.megaupload.com/?d=FI5EN692
mirror:
http://depositfiles.com/files/0zvajlqqr
http://hotfile.com/dl/113154364/ccab...ianOS.rar.html
http://uploading.com/files/9626d2e1/SymbianOS.rar/


Adaptation Layer:
http://www.megaupload.com/?d=YUNBJ8IW
mirror:
http://depositfiles.com/files/a35nsx6n1
http://hotfile.com/dl/113097015/8dfb...Adapt.rar.html


Symbian Middleware:
http://www.megaupload.com/?d=QZFUZ4L0
mirror:
http://depositfiles.com/files/fugtgycf7




Source code of the symbian^3 application(music player,screensaver,ecc.)
http://www.megaupload.com/?d=7MHQ9RP3
mirror:
http://depositfiles.com/files/z5sxtz9h6
http://hotfile.com/dl/113105376/4743...tions.rar.html


The source code of bootloader are inside of SymbianOS layer the folder is: os/kernelhwsvr/brbootldr




HOWEVER these files are over the internet for a very long time now (since nokia made symbian 3 open source and then closed it again).

The idea of an emulator like preenv is nice but i think it`s impossible - symbian is not even Linux