--- a/catalog.c
+++ b/catalog.c
@@ -68,10 +68,10 @@
 #define XML_URN_PUBID "urn:publicid:"
 #define XML_CATAL_BREAK ((xmlChar *) -1)
 #ifndef XML_XML_DEFAULT_CATALOG
-#define XML_XML_DEFAULT_CATALOG "file:///etc/xml/catalog"
+#define XML_XML_DEFAULT_CATALOG "file://@GENTOO_PORTAGE_EPREFIX@/etc/xml/catalog"
 #endif
 #ifndef XML_SGML_DEFAULT_CATALOG
-#define XML_SGML_DEFAULT_CATALOG "file:///etc/sgml/catalog"
+#define XML_SGML_DEFAULT_CATALOG "file://@GENTOO_PORTAGE_EPREFIX@/etc/sgml/catalog"
 #endif
 
 #if defined(_WIN32) && defined(_MSC_VER)
@@ -76,7 +76,7 @@
 
 #if defined(_WIN32) && defined(_MSC_VER)
 #undef XML_XML_DEFAULT_CATALOG
-static char XML_XML_DEFAULT_CATALOG[256] = "file:///etc/xml/catalog";
+static char XML_XML_DEFAULT_CATALOG[256] = "file://@GENTOO_PORTAGE_EPREFIX@/etc/xml/catalog";
 #if defined(_WIN32_WCE)
 /* Windows CE don't have a A variant */
 #define GetModuleHandleA GetModuleHandle
--- a/xmlcatalog.c
+++ b/xmlcatalog.c
@@ -43,7 +43,7 @@
 
 
 #ifndef XML_SGML_DEFAULT_CATALOG
-#define XML_SGML_DEFAULT_CATALOG "/etc/sgml/catalog"
+#define XML_SGML_DEFAULT_CATALOG "@GENTOO_PORTAGE_EPREFIX@/etc/sgml/catalog"
 #endif
 
 /************************************************************************
--- a/runtest.c
+++ b/runtest.c
@@ -2747,7 +2747,7 @@
  */
 static int
 uripMatch(const char * URI) {
-    if ((URI == NULL) || (!strcmp(URI, "file:///etc/xml/catalog")))
+    if ((URI == NULL) || (!strcmp(URI, "file://@GENTOO_PORTAGE_EPREFIX@/etc/xml/catalog")))
         return(0);
     /* Verify we received the escaped URL */
     if (strcmp(urip_rcvsURLs[urip_current], URI))
@@ -2766,7 +2766,7 @@
  */
 static void *
 uripOpen(const char * URI) {
-    if ((URI == NULL) || (!strcmp(URI, "file:///etc/xml/catalog")))
+    if ((URI == NULL) || (!strcmp(URI, "file://@GENTOO_PORTAGE_EPREFIX@/etc/xml/catalog")))
         return(NULL);
     /* Verify we received the escaped URL */
     if (strcmp(urip_rcvsURLs[urip_current], URI))
--- a/xmllint.c
+++ b/xmllint.c
@@ -103,7 +103,7 @@
 #endif
 
 #ifndef XML_XML_DEFAULT_CATALOG
-#define XML_XML_DEFAULT_CATALOG "file:///etc/xml/catalog"
+#define XML_XML_DEFAULT_CATALOG "file://@GENTOO_PORTAGE_EPREFIX@/etc/xml/catalog"
 #endif
 
 typedef enum {