Hi guys,
I have 1G RAM on the BaaN server. 77-80% of Mem usage is for sqlservr.exe so I have only 50M RAM available. :(
Is this normal?
Thanks.

Yep, SQL Server uses as much memory as it can so that it can cache tables in memory for faster access. There are settings to tweak this though.

Could you tell me where are the settings?

This document will help you

in enterprise manager there is an option to either allow sql to use the memory in dynamic mode or allocate a specific amount of memory to sql. I found on SQL7 that if it was in dynamic mode the server would lock up after about 3 weeks. once allocated the memory the problem went away.