i need help with IE
 

in my new forum Version 4.0.3
every thing great if i am using fire fox .
BUT WHEN I USE intenet explorer , many problems came !
1- when a user wanna regester and while he is typling the user name in fire fox if the user name regestred it show a box tell ( that user name already regstred ) but in IE nothing show !

2- when a user loged its give a massage tell ( if ur browser did not redirext u click here ) in fire fox it redireect , in IE no ..user must click to go ,..,..

3- in fire fox quick replay icons works , in IE NO !

4- changeing theam in IE donot make any effict , but in fire fox normal

5- face book fast rigester in my forum with ie now apprer but with fire fox show ...
what problem ppl ? how 2 fix