Firefox is occasionally breaking the back button -

There is a very disappointing time with the Firefox and the back button ... This is the simple ASP form:

  & lt; Top & gt; & Lt; Title & gt; Form 1 & lt; / Title & gt; & Lt; / Head & gt; & Lt; Body & gt; & Lt; Form action = "form2.asp" method = "post" & gt; Enter some text: & lt; Input type = "text" name = "thetext" id = "thetext" & gt; & Lt; Input type = "submit" id = "submit" name = "submit" & gt; & Lt; / Form & gt; & Lt; / Body & gt; & Lt; / Html & gt;  

Firefox (3.6.3) will sometimes clear the value of the text box after the submit button is pressed, and then back button when it strikes it is unpredictable, and it has dozens Will work hundreds of times, and then suddenly it stops working.

Any ideas where I should?