The command or action 'Paste' isn't available now

[xbs]

An odd bug, and I was wondering if someone had a workaround or even an
explanation.
I have a simple form (Form1) with one text box. If I run the following line
of code. "DoCmd.OpenForm "Form1",acNormal,,,,acDialog", the form opens in
dialog mode. If I use the Office Clipboard Toolbar (using Excel 2000 and
Access 2000) and paste an entry into the text box, I get the following
error:

The command or action 'Paste' isn't available now.
*You may be in a read-only database or an unconverted database from an
earlier version of [ProductName].
* The type of object the action applies to isn't currently selected or isn't
in the active view.
Use only theose commands and macro actions that are currently available for
this database.

Strangely enough, I can copy (Ctrl-C) and paste (Ctrl-V) into it fine. Also,
if I open the form in acWindowNormal mode (the default), the Office
Clipboard Toolbar works as expected.
Unfortunately, given the situation, neither opening the form in
acWindowNormal mode nor telling the user not to use the Office Clipboard
Toolbar is an option.

Thanks in advance for any thoughts...