faxmail problem

["azeem ahmad" <azeem81 msn com>]

hi list
i m configuring hylafax as mail to fax gateway.
but its not working properly
when i send mail to zonifax zoni com it gives me that error back which is 
shown below
/etc/aliases file entry is as below
zonifax: "|/usr/bin/faxmail -d fax 5848156"
-----------------------------------------------------------------------------------------------------------------------------------
The original message was received at Wed, 1 Feb 2006 16:53:49 +0500 from 
[192.168.10.12]

  ----- The following addresses had permanent fatal errors ----- 
"|/usr/bin/faxmail -d fax 5841019"
   (reason: Service unavailable)
   (expanded from: <zonifax zoni com>)

  ----- Transcript of session follows -----
smrsh: "faxmail" not available for sendmail programs (stat failed) 554 5.0.0 
Service unavailable
-----------------------------------------------------------------------------------------------------------------------------------

what should be done
Regards
Azeem