I got an error I can't begin to understand when running the patch for group pricing on a new install of 1.3.5 (previously installed group pricing on a different installation of 1.3.2 without any problems). The patch -p0 < group_pricing.patch returned:

patching file ./admin/customers.php
Hunk #1 succeeded at 824 with fuzz 2 (offset -6 lines).
patching file ./admin/group_pricing.php
patching file ./admin/includes/languages/english/document_product.php
patching file ./admin/includes/languages/english/product.php
patching file ./admin/includes/modules/product/collect_info.php
Hunk #4 succeeded at 205 (offset 3 lines).
Hunk #6 succeeded at 257 (offset 3 lines).
patching file ./admin/includes/modules/update_product.php
Hunk #3 succeeded at 209 (offset 5 lines).
patching file ./includes/classes/shopping_cart.php
Hunk #5 succeeded at 1079 (offset 20 lines).
Hunk #6 succeeded at 1078 with fuzz 2.
Hunk #7 succeeded at 1120 (offset 20 lines).
patching file ./includes/functions/functions_prices.php
Hunk #1 FAILED at 1.
1 out of 1 hunk FAILED -- saving rejects to file ./includes/functions/functions_prices.php.rej
patching file ./test.patch

Pretty desperate to get this working properly... ANY help would be greatly appreciated!