I happened upon a slick extensible UML tool for Windows called UMLStudio and
liked it enough to write a script to generate Ada 95 code from the diagrams.
It doesn't reverse engineer Ada but if enough of us asked, perhaps they would!

See www.pragsoft.com\download.html  for both the script and a trial version of
the program.  Let them know that Ada reverse engineering would be worthwhile!

PS: I get no compensation from them and have no stake in their company.

Patrick Rogers
Technical Editor, Ada Letters