diff --git a/src/err.c b/src/err.c
index 366c34d7..8c6262e5 100644
--- a/src/err.c
+++ b/src/err.c
@@ -183,11 +183,14 @@ void err_setdest(char *cvalue, int destination) {
 extern int err_setdebugmask(char *list) {
     unsigned int rack;
     char *token, *str, *last;
+    char *tmpstr;
     int index;
 
     err_debugmask=0x80000000; /* always log L_MISC! */
-    str=list;
-
+    str=tmpstr=strdup(list);
+    if(!str)
+	return 0;
+    
     while(1) {
         token=strtok_r(str,",",&last);
         str=NULL;
@@ -203,6 +206,7 @@ extern int err_setdebugmask(char *list) {
 
             if(!err_categorylist[index]) {
                 DPRINTF(E_LOG,L_MISC,"Unknown module: %s\n",token);
+		free(tmpstr);
                 return 1;
             } else {
                 DPRINTF(E_DBG,L_MISC,"Adding module %s to debug list (0x%08x)\n",token,rack);
@@ -212,6 +216,7 @@ extern int err_setdebugmask(char *list) {
     }
 
     DPRINTF(E_INF,L_MISC,"Debug mask is 0x%08x\n",err_debugmask);
+    free(tmpstr);
 
     return 0;
 }