rocks.jpgPrivate equity buyouts of Clear Channel and BCE have already gone to court due to tightening credit markets, and now it looks like Apollo Management’s $6.5 billion buyout of U.S. chemical company Huntsman Corp may be next. Apollo’s Hexion Speciality Chemicals filed a lawsuit against Huntsman on Wednesday that would seek to limit its liability if the deal falls apart, saying financing for the buyout– one of the last still to close from the private equity boom of 2007 — was in jeopardy because of Huntsman’s weakened financial position. Huntsman called the move “a blatant attempt to deprive our shareholders,” and a countersuit seems to be all but inevitable.

Spanish retail bank Santander is looking at taking over insurer Allianz’s loss-making Dresdner Bank, according to sources familiar with the matter. Commerzbank, Germany’s second-biggest bank, is already in advanced talks about a deal with Dresdner. But foreign banks like Santander are keen not to miss a rare chance to get a foothold in Europe’s biggest economy, whose banking market is largely closed to outsiders because of the dominance of not-for-profit community savings banks.The Dresdner sale is only part of the merger mania in Germany’s banking sector: Top retail bank Deutsche Postbank is also up for sale and Citigroup is selling its retail business here.

Vodafone has dropped out of the auction for Tiscali, according to the the Financial Times, driving the Italian broadband company’s shares down more than 9 percent. Vodafone had been seen as the most likely buyer for Tiscali as it could acquire both the Italian and British divisions to combine them with existing assets. BSkyB and Carphone Warehouse, Italy’s Wind and Swisscom are still in the frame, and the FT said that Vodafone could even re-enter the process if an agreement with the remaining bidders could not be reached. At a time of tight credit markets, slowing consumer spending and flagging broadband growth, it seems that bidders can afford to play hardball.

More Deals of the Day:

** Google Inc and Yahoo Inc face intense U.S. Justice Department scrutiny of their deal to share some advertising revenue, and the heat will likely increase under a new administration, antitrust experts said.

** French drugmaker Sanofi-Aventis plans to make a 40.04 billion crown ($2.6 billion) offer for Czech drugmaker Zentiva trumping a bid from financial group PPF. ** Miner BHP Billiton Plc/Ltd is due to file with Chinese competition authorities this month for its planned $170 billion takeover of Rio Tinto Plc/Ltd, but lawyers said a new anti-monopoly law threw up uncertainties.