vacuuming large Illustra db's

We're running Illustra 3.3 (and previously 3.2) on solaris 2.5, using the 2D and 3D spatial datablades. We are finding (with either version) that if our databases are sufficiently large (around 100-200 MB), then "vacuum all" will consistently fail with an "Internal Error" after the first few seconds. We even are finding that a new database with freshly loaded records (with very few deletes or updates) will fail on vacuum. As anyone experienced this problem? Our current workaround is to copy out the important tables, drop and recreate the database (and manually remove the stripe directory contents - Illustra doesn't do that for you (arghh!) ) and then copy the tables back in. Does anyone have a more elegant solution? Thanks, Mike Dunham-Wilkie