Index: openacs-4/packages/invoices/www/invoice-cancellation.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/invoices/www/invoice-cancellation.tcl,v
diff -u -r1.6 -r1.7
--- openacs-4/packages/invoices/www/invoice-cancellation.tcl	2 Apr 2006 22:08:02 -0000	1.6
+++ openacs-4/packages/invoices/www/invoice-cancellation.tcl	2 May 2006 12:07:11 -0000	1.7
@@ -96,24 +96,27 @@
 	set parent_item_id [content::revision::item_id -revision_id $parent_id]
 	db_1row get_credit_offer {}
 
-	if {[db_0or1row get_old_credit {}] && $old_credit > 0.} {
+	if {[db_0or1row get_old_credit {}] && $old_credit < 0.} {
 	    # cancelled invoice has credit
 	    set invoice_id [content::revision::item_id -revision_id $new_invoice_rev_id]
-	    set total_credit "-$old_credit"
+	    set total_credit [expr -1. * $old_credit]
 	    set vat_credit [format "%.2f" [expr $total_credit * $vat_percent / 100.]]
 
 	    # add new offer item
+	    set credit_category_id [parameter::get -parameter "CreditCategory"]
 	    set offer_item_rev_id [iv::offer_item::new \
 				       -offer_id $credit_offer_rev_id \
 				       -title $title \
 				       -description $description \
 				       -comment "" \
 				       -item_nr $invoice_id \
-				       -item_units 1 \
-				       -price_per_unit $total_credit \
+				       -item_units $total_credit \
+				       -price_per_unit 1 \
 				       -rebate 0 \
 				       -sort_order $invoice_id \
 				       -vat $vat_credit]
+
+	    category::map_object -object_id $offer_item_rev_id $credit_category_id
 	}
 
 	if {[exists_and_not_null category_ids]} {