asterisk users - Apr 2006 - IVR and voicemail issues ?

Hi,

I have this setup in my extensions.conf:

[inbound-analog]
exten => s,1,Answer
exten => s,2,SetMusicOnHold(default)
exten => s,3,DigitTimeout,5
exten => s,4,ResponseTimeout,10
exten => s,5,Background(tag-welcome)

exten => 1,1,Voicemail(u100)
exten => 1,2,Hangup 'Zap/1-1'

this means - press 1 and it goes to voicemail for extension 100.
It all works well - except when you hangup.  It does not clear the Zap/1-1
interface.  It keeps it open - indefinitly.

I read to use DeadAGI ? But could not figure this out - I am new to
asterisk ;)

Can anyone help ?
Thanks
Tonino