SQL Connection help needed

I'm using visual studio 2005 and SQL 2000, trying to connect to a sql
database as a differnent user.

Here is my current connection string that is using my own NT login:

Dim message As String = "Data Source=" +
Me.ComboBox1.Text.ToString() + ";Initial Catalog=Store;Integrated
Security=SSPI"
Dim sql As New SqlClient.SqlConnection(message)

sql.Open()

I have access to this database and the connection establishes fine.
However i dont have access to certain Stored Procedure's on this
database and these run through a differnt NT user.

I dont have access to a SQL user name and password so i cant hardcode
the "sa" login instead.

Does anyone know if i can change my connection string above to use
another windows/NT login?

Awaiting reply,
Andy

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