Balsa won't lock my /var/spool/mail/user file

[andy clark convergys com]

I have installed Balsa 1.0, and set it up to look straight at my ISP's
mailserver as well as my local mail file (/vcar/spool/mail/user), but when it
tries to check for new mail it gives me an error like:
     can't lock mailbox /var/spool/mail/user

has anyone got a workaround for this?

thanks,
andy.

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