uploading files button as image has probs... help

hello friends,

I am trying to upload files to server it is working fine when the form is normal like the one below:

<FORM name="f" ENCTYPE="multipart/form-data" ACTION="upload.php"" METHOD="POST"> <INPUT TYPE="hidden" name="MAX_FILE_SIZE" value="10000"> <INPUT NAME="userfile" TYPE="file">
<INPUT TYPE="submit" VALUE="Send File">
</FORM>

but the look is not so nice. so i tried using some images as buttons.

i have three two buttons browse and upload which are images

on click of browse button i am calling a function which call the browse window to select file from local system :

document.f.userfile.click();

on the click of upload image i am submitting the form:
document.f.submit();

It is giving an error saying :

Access Denied

It also gives the line no. of
document.f.submit();
as error line no.


Any help will be great

gowni