[Serusers] lookup("aliases") doesn't work

[JOHN J. BARTON]

At least on my server the error messages about lookup("aliases") and 
save("aliases") occur on the first time a user connects to confirm 
subscription, eg by clicking on the link sent to them by email. If the 
user clicks a second time, the error goes away.    Anyone else seen 
this?  Any idea how to fix it?  (My ser.cfg is very close to the default 
setup with mysql enabled).

John.