Nomura Holdings, Japan's biggest brokerage, has also taken the oppportunity of Wall Street's meltdown to swoop, buying the operations of failed Morgan rival Lehman Brothers in Europe, the Middle East and Asia.

When asked for comment for this story, a Morgan Stanley spokesman said: "This deal is a strategic alliance with numerous opportunities for global collaboration and both sides are moving ahead quickly to close the transaction".

Mitsubishi UFJ will receive a board seat at Morgan Stanley.

"The point of this is to strengthen our alliance with Morgan Stanley. This is completely a strategic investment," said a spokesman for Mitsubishi UFJ.

Fair enough. But as history has indicated, it's going to take time, and it's not going to be easy -- if it ever happens at all.

"I think that without majority control it is very hard for them to really do anything on the business side, to really change the business," said KBC's Li.