[LDTP-Dev] ATOMac Ldtp. 'Core' object has no attribute '_callback_event'

[Polly]

Hi, everyone

I am new to LDTP. I write a simple java application to test GUI using ldtp library.
Application successfully works on Win7, Ubuntu10.4  and SLES11. But i can't to start it on Mac 10.6.
It crashes with following error:

Exception in thread "Thread-4" com.cobra.ldtp.LdtpExecutionError: <type 'exceptions.AttributeError'>:'Core' object has no attribute '_callback_event'
	at com.cobra.ldtp.Ldtp.getString(Ldtp.java:260)
	at com.cobra.ldtp.Ldtp.pollEvents(Ldtp.java:701)
	at com.cobra.ldtp.PollEvents.run(PollEvents.java:88)

I have no idea what is wrong.
So, could anyone help me?

Many thanks,
Polly.