diff --git a/build_tools/cflags.xml b/build_tools/cflags.xml
index db140d6aae..b027cb017d 100644
--- a/build_tools/cflags.xml
+++ b/build_tools/cflags.xml
@@ -13,6 +13,8 @@
 		</member>
 		<member name="STATIC_BUILD" displayname="Build static binaries">
 		</member>
+		<member name="IAX_OLD_FIND" displayname="Use the old, slow method of searching for IAX callnos">
+		</member>
 		<member name="LOADABLE_MODULES" displayname="Runtime module loading">
 			<defaultenabled>yes</defaultenabled>
 		</member>
diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index 9f30359e2c..9234a5d177 100644
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -1563,6 +1563,7 @@ static int __find_callno(unsigned short callno, unsigned short dcallno, struct s
 			return res;
 		}
 
+#ifdef IAX_OLD_FIND
 		/* If we get here, we SHOULD NOT find a call structure for this
 		   callno; if we do, it means that there is a call structure that
 		   has a peer callno but did NOT get entered into the hash table,
@@ -1601,6 +1602,7 @@ static int __find_callno(unsigned short callno, unsigned short dcallno, struct s
 		if (res) {
 			ast_log(LOG_WARNING, "Old call search code found call number %d that was not in hash table!\n", res);
 		}
+#endif
 	}
 	if (!res && (new >= NEW_ALLOW)) {
 		int start, found = 0;