[vchkpw] [SPAM] How can I disable "user over quota" message?

[Bulend Kolay]

Hello

I use vpopmail on qmail.
As default, when a mail account reaches to its quota,  vpopmail sends a 
warning message  to sender addres about "user over quota".
How can I disable to send these warning messages to sender?
I think this condition causes backscatter.
any advice?
Thanks



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