z39.50 not working: Can't load Z3950/ZOOM/ZOOM.dll

[MarekZ ()]

I installed KOHA 2.2.9 on XP, (with Yaz module included), and initially the Z39.50 search worked (for about a week). Then it stopped. I tried the remedies found in this group, then uninstalled and re-installed KOHA, then installed new Yaz, all with the same result. The error in the intranet error log is:

Can't load 'C:/usr/site/lib/auto/Net/Z3950/ZOOM/ZOOM.dll' for module Net::Z3950::ZOOM: load_file:The specified procedure could not be found at C:/usr/site/lib/XSLoader.pm line 70.,
[Tue Jul 07 11:41:05 2009] [error] [client 192.168.1.100]  at C:/usr/site/lib/Net/Z3950/ZOOM.pm line 12, referer: http://kura:8080/cgi-bin/koha/acqui.simple/addbiblio.pl
[Tue Jul 07 11:41:05 2009] [error] [client 192.168.1.100] Compilation failed in require at C:/usr/site/lib/ZOOM.pm line 6.
[Tue Jul 07 11:41:05 2009] [error] [client 192.168.1.100] BEGIN failed--compilation aborted at C:/usr/site/lib/ZOOM.pm line 6.
[Tue Jul 07 11:41:05 2009] [error] [client 192.168.1.100] Compilation failed in require at C:/usr/koha229/intranet/cgi-bin/koha/z3950/search.pl line 30.
[Tue Jul 07 11:41:05 2009] [error] [client 192.168.1.100] BEGIN failed--compilation aborted at C:/usr/koha229/intranet/cgi-bin/koha/z3950/search.pl line 30.

It is path problem? I checked, then retyped the path, rebooted the computer. The path is below.

PATH=C:\MYSQL\BIN;C:\usr\site\bin;C:\usr\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\W
INDOWS\System32\Wbem;C:\Program Files\ATI Technologies\ATI.ACE\;C:\Program Files
\Common Files\Roxio Shared\DLLShared\;C:\Program Files\Common Files\Roxio Shared
\9.0\DLLShared\;C:\strawberry\c\bin;C:\Program Files\Yaz\bin

I renamed the Yaz directory, and installed new Yaz 3.0.46. The same error as above.

Is it firewall?

Disabled Zone Alarm firewall - the same.

Used Yaz from command line - connects OK,

C:\Documents and Settings\Marek>yaz-client.exe
Z> open z3950.loc.gov:7090/Voyager
Connecting...OK.
Sent initrequest.
Connection accepted by v3 target.
ID     : 34
Name   : Voyager LMS - Z39.50 Server (YAZ Proxy)
Version: 2006.5.2/1.2.1.1
Options: search present

The MarcEdit program also connects with z39.50 servers without problems.

It is possible, that the error is different each time, but how to find out? Is there any diagnostics I can use? Does anybody have a clue, what else can I check?

I would appreciate any help or suggestions. I still hope to use KOHA to manage our non-profit institute 25 thousand volume library...

Thanks - Marek