InDesign CS 3.01, Windows 2000

When I zoom with Ctrl-Spacebar I get weird things happening.

Sometimes it works as it is supposed to.

Half the time, it zooms in on the area where the cursor is, not on the
area I marked with the mouse. When this happens it adds a space into
wherever the cursor is. When it works correctly (zooms on the area I
marked) it does not add a space to where the cursor is.

Has anyone else experienced this?

Bug?

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