diff --git a/statement.c b/statement.c
index da5abf5..a019d5d 100644
--- a/statement.c
+++ b/statement.c
@@ -581,6 +581,7 @@ SC_free_params(StatementClass *self, char option)
 	{
 		APD_free_params(SC_get_APDF(self), option);
 		IPD_free_params(SC_get_IPDF(self), option);
+		if (self->prepared!=NOT_YET_PREPARED) SC_set_prepared(self, NOT_YET_PREPARED);
 	}
 	PDATA_free_params(SC_get_PDTI(self), option);
 	self->data_at_exec = -1;