Poor performance with "select filter value" F4 help on web

We've noticed very poor performance when bringing up the "select filter value" box (F4 help) on web reports. For example, when filtering on Profit Center, it will take about 2-3 minutes for the dialog box to appear, even though we only have about 600 profit centers. If a hierarchy is activated, it only takes a couple seconds for the box to appear.

We're running BW 3.0B SP25 on DB/2. We already tried implementing OSS note 808189, but that didn't fix the problem.

Has anyone had this problem before?