[You must have the WordPerfect Office X4 Hot Fix 2 installed. If you are using an older version of WordPerfect, you must produce a PDF and then convert it to PDF/A]
From the File menu, select Publish to PDF, and click the Settings button:
Select PDF/A-1a from the “Compatibility” drop-down and click OK:
Click OK to return to the “Publish to PDF” screen to complete document production. The compatibility setting will remain set to PDF/A until you change it.