diff --git a/src/eap_peer/tncc.c b/src/eap_peer/tncc.c
index a3ec39514..3fb3f163f 100644
--- a/src/eap_peer/tncc.c
+++ b/src/eap_peer/tncc.c
@@ -25,7 +25,9 @@
 #endif /* UNICODE */
 
 
+#ifndef TNC_CONFIG_FILE
 #define TNC_CONFIG_FILE "/etc/tnc_config"
+#endif /* TNC_CONFIG_FILE */
 #define TNC_WINREG_PATH TEXT("SOFTWARE\\Trusted Computing Group\\TNC\\IMCs")
 #define IF_TNCCS_START \
 "<?xml version=\"1.0\"?>\n" \
diff --git a/src/eap_server/tncs.c b/src/eap_server/tncs.c
index e429f1e67..c6c71c578 100644
--- a/src/eap_server/tncs.c
+++ b/src/eap_server/tncs.c
@@ -19,7 +19,9 @@
 /* TODO: TNCS must be thread-safe; review the code and add locking etc. if
  * needed.. */
 
+#ifndef TNC_CONFIG_FILE
 #define TNC_CONFIG_FILE "/etc/tnc_config"
+#endif /* TNC_CONFIG_FILE */
 #define IF_TNCCS_START \
 "<?xml version=\"1.0\"?>\n" \
 "<TNCCS-Batch BatchId=\"%d\" Recipient=\"TNCS\" " \