Japanese sheet import problem

Hi

I tried to import an excel sheet with japanese contents inside. It took some time to load and suddenly my firefox browser freezed. After a while there were multiple warning boxes displayed with ?????????????? junk characters. I quit all the warning box and could now see the excel sheet imported. I clicked on the imported sheet and again my browser freezed for sometime, then it displayed the sheet with the contents properly. But I could not navigate or edit the sheet. There were some more pop up warning messages with ?????????????? junk. Though the sheet was imported, a message said that the import failed and I was logged out? I am just posting this so that it may be useful for you guys to fix any double byte character processing problems.