Script of behaviorus plugin

[Yam Diet]

Hi! i'm using JIRA 6.3.9

I found good solution of my problem here: http://blogs.onresolve.com/2010/03/audo-duplicate-search-in-jira/

But when i tryed to copy script in "Add serverside script" i got this error: Compilation failure: startup failed: Script1.groovy: 16: unable to resolve class com.opensymphony.user.User @ line 16, column 1. import com.opensymphony.user.User ^ Script1.groovy: 7: unable to resolve class com.opensymphony.user.UserManager @ line 7, column 1. import com.opensymphony.user.UserManager ^ 2 errors

How can i use this script?

[Yam Diet]

I found out how to add it, found last version of .groovy Now it works, but how can i use it on custom fields?