The agent could not be started.

I created a snapshot publication (the engine is SQL2005 and the compatibility is 2000).
I got this message:

"The agent could not be started.
An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)
SQLServerAgent Error: Request to run job REPLSM-6 (from User DOM\custuser) refused because the job has been suspended.
Changed database context to SM. (Microsoft SQL Server, Error: 22022)"

And when i'm trying to reinitialize the publication, I get this:

"Replication Monitor could not start the Snapshot Agent to generate a new snapshot. You must start the Snapshot Agent manually before the subscription(s) can be reinitialized..."

What can I do? Why it doesn't work?
thnx