It's strange though that it can still actually create the feature, albeit from the old code! I'm using XP Pro x64 (SP2) and just opened a part with a swept-cut "Thread" feature that I'd recently created on 2009 SP 2.1, it opened fine in SP 3.0. However, when I deleted the swept-Cut and then used the same Helix and Profile to apply a new Swept-Cut it failed to work, showing a rebuild errors message, "Sweep operation failed to complete". I Dismissed the message by closing the feature properties with the Red X and then hit the Undo button and it recreated the deleted 2.1 feature OK. Maybe it just uses a stored "undo" image and doesn't recreate it!
Trevor Clarke. (R & D) Scientific Instruments.Somerset. UK
SW2009x64 SP3.0 Intel Core i7 2.94Ghz, 12Gb Ram, NVIDIA Quadro FX3700 Driver: 6.14.11.8246
SW2009x64 SP3.0 Intel Core 2 Duo 3.17Ghz, 8Gb Ram NVIDIA Quadro FX3700 Driver: 6.14.11.8246