Zugschlusbeobachtungen

Dear lazyweb, how do I pin lenny now and have that pin hold after lenny's release?

• Codename lenny doesn't work, apt cannot do this (#433624, 18 months old, without any reaction yet)
• Version 5.0 doesn't work, lenny's Release file doesn't have a Version field yet
• Suite testing will match lenny now and then track squeeze once squeeze is testing

Is there any method that will get me testing lenny now and stable lenny later and not testing squeeze?