anchors put after query strings in dynamic pages

(hit and miss usage - why?)

[nevdev]

I'm having trouble using anchor tags at the end of query strings.

I've got links like this in a page which is dynamically created by PHP:

<a href="products.php?chosencat=Apples#F06">apples variety 6</a>

...to get to this anchor on another dynamically created page (products.php):

<a name="F06" id="F06"></a>

...but the use of this is hit-or-miss: sometimes the browser displays the page at the correct anchor, sometimes it doesn't.

What am I doing wrong?

[nevdev]

I ought to have added that refreshing the target page causes the correct anchor-position to be displayed..

[nevdev]

Correction: only the odd hack of placing the cursor after the end of the string, and hitting return, and in FireFox only (!) as far as I can see, will cause it to go the right place (clicking the refresh icon is no good). All attempts in other browsers show the hit-and-mis results. I'm stumped.

[nevdev]

I realised I made anchor names with numbers, but when I ensure they are alpha strings, and also that the anchors have content on the target page, the link still doesn't find the right place in the page! Has anyone any sort of clue what might be wrong?