You can mitigate this problem by upgrading to Adobe Reader 8.
Alternatively, you can implement a workaround in your browser so that it does not use the Acrobat Reader plugin. The following instructions apply to the Firefox browser:
• In the Tools menu, select Options.
• Select Downloads in the Options dialog.
• Click on the View & Edit Actions button.
• In the Download Actions dialog, choose the action for the PDF extension or the Adobe Acrobat Document file type and then click on Change Action.