PostgreSQL 8.1: createdb: xflush error ?

Hi,

 

I'm trying to make a new database, yet when I try to do this I get the following error:

 

ERROR:  xlog flush request 0/827520 is not satisfied --- flushed only to 0/80D7B8
CONTEXT:  writing block 5 of relation 1663/16893/1259

 

Can someone give me a clue of what it means ?

 

Regards,

Steven