Another fix for the textarea, for Opera browser this time. It seems that when applying the script to a textarea that already contains text on page load, the character counting gets all wrong, counting many extra characters for each line break.
The fix is only three lines of code, but it took a while to figure: First we extract the textarea's innerHTML into a variable (not the value attribute, it has to be the html). in this variable, we replace "\r\n" by "\n" with a regular expression, otherwise the count would still be wrong. Then we erase the textarea innerHTML, and finally, we put back the variable's content into the textarea's value attribute. A total hack, but it fixes it.

Also, added a small improvement with IE. Sometimes the textarea do not expend enough to show all the content with no scroll bar, so we added extra space, just for IE.