diff --git a/tests/Makefile.am b/tests/Makefile.am
index 1595a07e..e82647f1 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -33,6 +33,7 @@ tbf_TbfTest_LDADD = \
 	$(LIBOSMOGSM_LIBS) \
 	$(LIBOSMOCORE_LIBS) \
 	$(COMMON_LA)
+tbf_TbfTest_LDFLAGS = -Wl,--wrap=pcu_sock_send
 
 bitcomp_BitcompTest_SOURCES = bitcomp/BitcompTest.cpp ../src/egprs_rlc_compression.cpp
 bitcomp_BitcompTest_LDADD = \
diff --git a/tests/tbf/TbfTest.cpp b/tests/tbf/TbfTest.cpp
index 46863e36..aa1d7ac5 100644
--- a/tests/tbf/TbfTest.cpp
+++ b/tests/tbf/TbfTest.cpp
@@ -137,7 +137,9 @@ static void test_tbf_tlli_update()
 
 static uint8_t llc_data[200];
 
-int pcu_sock_send(struct msgb *msg)
+/* override, requires '-Wl,--wrap=pcu_sock_send' */
+int __real_pcu_sock_send(struct msgb *msg);
+int __wrap_pcu_sock_send(struct msgb *msg)
 {
 	return 0;
 }