Including "add to cart" button in web page - out of stock?

[MoGrafixation]

Hi all

We're using Catalog v7.0.6.0.0.0.GBGA

We have a main site (http://www.the-company.com) and a subdomain for the Actinic shop (http://shop.the-company.com)
We're trying to include "add to cart" buttons from the main site's discography, it's a musician's site.
All is fine until we link the button to an item that's not currently in stock.

This one is in stock and works

<a href="http://shop.the-company.com/cgi-bin/ca000010.pl?SID=7&PAGE=PRODUCT&Q_CDVD%2F0215=1&ACTINIC_REFERRER=http://shop.the-company.com/acatalog/"><img src="http://shop.the-company.com/acatalog/addtocart.gif" name="CDS1%2F0215" width="69" height="15" border="0" alt="Add To Cart"></a>

Without <...> so you can read it more easily without scrolling across:
a href="http://shop.the-company.com/cgi-bin/ca000010.pl?SID=7&PAGE=PRODUCT&Q_CDVD%2F0215=1&ACTINIC_REFERRER=http://shop.the-company.com/acatalog/"><img src="http://shop.the-company.com/acatalog/addtocart.gif" name="CDS1%2F0215" width="69" height="15" border="0" alt="Add To Cart"

This one is out of stock (but might come back)

<a href="http://shop.the-company.com/cgi-bin/ca000010.pl?SID=7&PAGE=PRODUCT&Q_CDVD%2F0046=1&ACTINIC_REFERRER=http://shop.the-company.com/acatalog/"><img src="http://shop.the-company.com/acatalog/addtocart.gif" name="CDS1%2F0046" width="69" height="15" border="0" alt="Add To Cart"></a>

a href="http://shop.the-company.com/cgi-bin/ca000010.pl?SID=7&PAGE=PRODUCT&Q_CDVD%2F0046=1&ACTINIC_REFERRER=http://shop.the-company.com/acatalog/"><img src="http://shop.the-company.com/acatalog/addtocart.gif" name="CDS1%2F0046" width="69" height="15" border="0" alt="Add To Cart"

For the out-of-stock item, we get this response:
"A General Script Error Occurred
Error: The specified product (reference CDVD/0046) has just been removed from the catalog. Please return to the catalog and continue shopping. If you press the Refresh or Reload button on your browser, the removed products will no longer be visible in the catalog. We apologize for the inconvenience."


Is there any way to make the button disappear when the item is out of stock, as it does now in our Actinic shop?
Or can we change the error message into a friendlier page? (OK but not best answer)
Would updating to v9 fix this?

Thanks for any help!

[MoGrafixation]

Update

Going to V9 (hurrah!) so might need advice with that if the problem remains!