What can justify 15 seconds of delay to retrive rows from system tables?

If I run select * from sysobjects, the first time it takes 15 seconds, after that it just takes 0 seconds. The same occurs with sp_helptext someAppSP or other stuff. Server is almost all time at 0% CPU usage.
It is a classic asp App on top of a VM with Microsoft SQL Server 2005 - 9.00.5000.00 (Intel X86) Dec 10 2010 10:56:29 Copyright (c) 1988-2005 Microsoft Corporation Standard Edition on Windows NT 6.1 (Build 7601: Service Pack 1)
I am after recent (newly) App's delays. I don't care the mentioned querys by itself.