Some days ago a new certification-document with an interesting info was updated:
Link to the certifications
In this excel-sheet is Forms 188.8.131.52 certified with JRE 1.7.0_04+. Very good news! And now we can hope, that Forms 11.1.2 gets the same certification soon, because this is the latest version available on OTN :
And last but not least: " Please Oracle, certify Oracle Forms 10g with JRE 7 ! "