diff --git a/parser/bignum.h b/parser/bignum.h
index 438294457..757da4964 100644
--- a/parser/bignum.h
+++ b/parser/bignum.h
@@ -59,11 +59,11 @@ public:
 		size_t i;
 		bool flag = true;
 		for (i = 0; i < 16; i++) {
-			if ((val[i] & 0xF0) >> 4 != 0)
+			if (flag && (val[i] & 0xF0) >> 4 != 0)
 				flag = false;
 			if (!flag)
 				data.push_back((val[i] & 0xF0) >> 4);
-			if ((val[i] & 0x0F) != 0)
+			if (flag && (val[i] & 0x0F) != 0)
 				flag = false;
 			if (!flag)
 				data.push_back(val[i] & 0x0F);
diff --git a/parser/parser_regex.c b/parser/parser_regex.c
index 440a1525e..7d1847692 100644
--- a/parser/parser_regex.c
+++ b/parser/parser_regex.c
@@ -886,7 +886,10 @@ static std::string generate_regex_range(bignum start, bignum end)
 	for (auto &i: regex_range) {
 		bignum sstart = i.first;
 		bignum send = i.second;
-
+		if (sstart.base == 16) {
+			for (j = (size_t) sstart.size(); j < 32; j++)
+				result << '0';
+		}
 		for (j = sstart.size() - 1; j >= 0; j--) {
 			result << std::nouppercase;
 			if (sstart[j] == send[j]) {