Mel Gibson wants to know what’s on Oksana Grigorieva’s 12-year-old son’s hard-drive, RadarOnline.com has exclusively learned.

We’re told lawyers for the embattled star are moving to subpoena Sascha’s computer in a bid to determine if Oksana transmitted those infamous audio tapes on the same laptop the child uses for his homework!

Oksana's lawyers will ask the court to stop the move, and will file a motion to quash the request, according to sources connected with the case.

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It was Mel Gibson who wanted to yank baby daughter Lucia's passport, not his scorned ex-lover Oksana Grigorieva, RadarOnline.com has exclusively learned.

The disgraced actor's legal team attempted to have Oksana surrender the eight-month-old's passport while their bitter court battles brews, but their move failed.