There is somthing really wrong with my keyboard - half the time it doesn't copy/paste...

I was trying to post a different method after my initial response. The GetRolesByUser is deprecated and should not be used at all.

The method you should use is GetUserRoles(PortalId, UserId)

This one returns an array list of UserRoleInfo objects. Iterating thru that array list, you can extract futher info about roles, i.e.:

                Dim userRoles_ As ArrayList = New DotNetNuke.Security.Roles.RoleController().GetUserRoles(PortalId, UserId)
                Dim ids_ As String = String.Empty

                For Each role_ As UserRoleInfo In userRoles_
                    ids_ += role_.RoleID + ";"
                Next