Index: res/snmp/agent.c
===================================================================
--- res/snmp/agent.c    (revision 48593)
+++ res/snmp/agent.c    (working copy)
@@ -478,7 +478,7 @@
                ret = (u_char *)&long_ret;
                break;
        case ASTCHANVARIABLES:
-               if (pbx_builtin_serialize_variables(chan, string_ret, sizeof(string_ret))) {
+               if (pbx_builtin_serialize_variables(chan, string_ret)) {
                        *var_len = strlen(string_ret);
                        ret = (u_char *)string_ret;
                }