Oksana Grigorieva's Newest Lawyer Angry at Mel Gibson, TMZ

Lisa Bloom claims "Mel has a fleet of highly aggressive law firms fighting her at every turn, including one which calls itself a '450+ lawyer business litigation firm -- the largest in the United States devoted solely to business litigation.'"

Although the current war is over custody, support and alleged crimes and not business litigation, Bloom adds, "This is only one of at least four known major law firms behind the scenes, as well as publicists, marketers, and public relations agencies." Bloom says, "Oksana is a single mother of two who's gone into debt fighting for simple justice."

TMZ broke the story ... at least 18 of Oksana's lawyers have submitted bills to the court totaling more than $1 million, and they've asked the judge to make Mel foot the bill.

Bloom says Oksana has had only "a handful" of different law firms in this case, adding, "Though occasionally other lawyers in their firms may have pitched in." Bloom says, "It is totally false to say she's had 39 lawyers." We have listed all 39 lawyers -- Bloom has not said which of the 39 she believes were not working on the case.