I tried to attach to weblogic 9. I followed instruction in attach wizard and
changed start script of weblogic. Attach wizard adviced me to set variabled 
JAVA_VENDOR, JAVA_HOME and JAVA_OPTIONS somewhere in the middle of weblogic
script. It didn't work, because first part of script was executed with JAVA_HOME
set to java home provided by weblogic and rest of script was executed with
JAVA_HOME set to sun java. I therefore moved the settings to the beginning of
the script, but I didn't notice that I moved it before SETLOCAL command and
arguments was again and again added to JAVA_OPTIONS each time when script was
executed so I had to move it right below SETLOCAL command. 

Then I find out that JAVA_HOME is still changed and it's changed in
setDomainEnv.cmd, where JAVA_HOME is set depending on property JAVA_VENDOR and
for JAVA_VENDOR=Sun it's changed JAVA_HOME to sun java 1.5.0_03 bundled with
weblogic. So I had to modify also setDomainEnv.cmd.