Index: bom2.c
===================================================================
--- bom2.c	(revision 37992)
+++ bom2.c	(revision 37993)
@@ -295,6 +295,15 @@
 			append_clean(s, ctx->name);
 			return 0;
 		}
+		if (strncmp(*input, "prefix%", 7) == 0) {
+			const char *t;
+			*input += 7;
+
+			for(t = ctx->name; isalpha(*t); t++)
+				gds_append(s, *t);
+			return 0;
+		}
+
 		if (strncmp(*input, "footprint%", 10) == 0) {
 			*input += 10;
 			gds_append_str(s, ctx->footprint);
@@ -402,7 +411,7 @@
 		const char *refdes = RND_UNKNOWN(pcb_attribute_get(&subc->Attributes, "refdes"));
 
 		ctx.subc = subc;
-		ctx.name = (char *)RND_UNKNOWN(pcb_attribute_get(&subc->Attributes, "refdes"));
+		ctx.name = (char *)refdes;
 		ctx.footprint = (char *)RND_UNKNOWN(pcb_subc_name(subc, "export_bom2::footprint"));
 		ctx.value = (char *)RND_UNKNOWN(pcb_attribute_get(&subc->Attributes, "value"));
 
Index: export_bom2.conf
===================================================================
--- export_bom2.conf	(revision 37992)
+++ export_bom2.conf	(revision 37993)
@@ -13,7 +13,7 @@
 # Quantity, Description, Value, RefDes
 # --------------------------------------------
 }
-geda.subc2id = {%subc.footprint%__%subc.value%}
+geda.subc2id = {%subc.prefix%__%subc.footprint%__%subc.value%}
 geda.item = {%count%,"%subc.footprint%","%subc.value%",%names%
 }
 geda.footer = {}