There is not definitive document that says it will or will not work, but as long as you set the AP541N with settings that will work with the WAP 2000, this means 2.4Ghz and Wireless security that it can handle. From every thing I have seen it will work with the AP541N, they both have the same ability for security. WDS feature will not work between devices though. The WAP2000 doesn't support that feature set.
Cisco Small Business Support Center
Randy Manthey
CCNA, CCNA - Security