BBC iPlayer issue; Using Firefox and Internet Explorer

liquidlives

For some strange reason, I can watch programmes on the iPlayer site with Firefox, but with Internet Explorer I cannot as it says "you do not have Flash" (this message seems to appear for everything that requires Flash when using IE). Before I got Firefox I never got this message. In addition, I cannot download programmes with Firefox as it says "you need to install the Download Manager" but I can download them with Internet Explorer. Anyone know how to fix this? Am I not allowed to have Flash for Firefox and for IE at the same time or something?