diff --git a/DeepTrace.c b/DeepTrace.c
index 6d8a4ef..a9dfc44 100644
--- a/DeepTrace.c
+++ b/DeepTrace.c
@@ -114,7 +114,9 @@ ZEND_END_ARG_INFO()
 /* {{{ DeepTrace function table */
 const zend_function_entry DeepTrace_functions[] = {
 		PHP_FE(dt_phpinfo_mode, arginfo_dt_phpinfo_mode)
+#if DEEPTRACE_PHP_VERSION < 55
 		PHP_FE(dt_set_proctitle, arginfo_dt_set_proctitle)
+#endif
 		PHP_FE(dt_remove_include, arginfo_dt_remove_include)
 		PHP_FE(dt_inspect_zval, arginfo_dt_inspect_zval)
 
diff --git a/DeepTrace_misc.c b/DeepTrace_misc.c
index d43442e..51d74d2 100644
--- a/DeepTrace_misc.c
+++ b/DeepTrace_misc.c
@@ -21,6 +21,7 @@
 
 #include "php_DeepTrace.h"
 
+#if DEEPTRACE_PHP_VERSION < 55
 /* {{{ setproctitle */
 #ifndef DEEPTRACE_SYSTEM_PROVIDES_SETPROCTITLE
 static zend_bool setproctitle(char *title, int title_len TSRMLS_DC)
@@ -69,6 +70,7 @@ PHP_FUNCTION(dt_set_proctitle)
 #endif
 }
 /* }}} */
+#endif
 
 /* {{{ proto bool dt_phpinfo_mode(bool phpInfoAsText)
    Switches between text-only and HTML phpinfo() mode */
diff --git a/php_DeepTrace.h b/php_DeepTrace.h
index 392be7a..e906ae3 100644
--- a/php_DeepTrace.h
+++ b/php_DeepTrace.h
@@ -216,7 +216,9 @@ void DeepTrace_clear_all_functions_runtime_cache(TSRMLS_D);
 
 /* DeepTrace PHP functions */
 PHP_FUNCTION(dt_phpinfo_mode);
+#if DEEPTRACE_PHP_VERSION < 55
 PHP_FUNCTION(dt_set_proctitle);
+#endif
 PHP_FUNCTION(dt_exit_mode);
 PHP_FUNCTION(dt_exit_fetch_exception);
 PHP_FUNCTION(dt_inspect_zval);