diff --git a/src/common/cvt.cpp b/src/common/cvt.cpp
index 1b7a55f7c7f..55cd17f659f 100644
--- a/src/common/cvt.cpp
+++ b/src/common/cvt.cpp
@@ -2872,6 +2872,16 @@ SSHORT CVT_decompose(const char* str, USHORT len, Int128* val, ErrorFunction err
 }
 
 
+Int128 CVT_hex_to_int128(const char* str, USHORT len)
+{
+	Int128 val;
+	RetValue<I128Traits> value(&val);
+	hex_to_value(str, str + len, &value);
+
+	return val;
+}
+
+
 USHORT CVT_get_string_ptr_common(const dsc* desc, USHORT* ttype, UCHAR** address,
 								 vary* temp, USHORT length, DecimalStatus decSt, Callbacks* cb)
 {
@@ -3538,7 +3548,7 @@ static void hex_to_value(const char*& string, const char* end, RetPtr* retValue)
  * Functional description
  *      Convert a hex string to a numeric value. This code only
  *      converts a hex string into a numeric value, and the
- *      biggest hex string supported must fit into a BIGINT.
+ *      size of biggest hex string depends upon RetPtr.
  *
  *************************************/
 {
diff --git a/src/common/cvt.h b/src/common/cvt.h
index f656194fbc8..04923f99b89 100644
--- a/src/common/cvt.h
+++ b/src/common/cvt.h
@@ -93,6 +93,7 @@ double CVT_get_double(const dsc*, Firebird::DecimalStatus, ErrorFunction, bool*
 Firebird::Decimal64 CVT_get_dec64(const dsc*, Firebird::DecimalStatus, ErrorFunction);
 Firebird::Decimal128 CVT_get_dec128(const dsc*, Firebird::DecimalStatus, ErrorFunction);
 Firebird::Int128 CVT_get_int128(const dsc*, SSHORT, Firebird::DecimalStatus, ErrorFunction);
+Firebird::Int128 CVT_hex_to_int128(const char* str, USHORT len);
 USHORT CVT_make_string(const dsc*, USHORT, const char**, vary*, USHORT, Firebird::DecimalStatus, ErrorFunction);
 void CVT_make_null_string(const dsc*, USHORT, const char**, vary*, USHORT, Firebird::DecimalStatus, ErrorFunction);
 void CVT_move_common(const dsc*, dsc*, Firebird::DecimalStatus, Firebird::Callbacks*);
diff --git a/src/dsql/Parser.cpp b/src/dsql/Parser.cpp
index 7e5eeff2f7b..bacacc63784 100644
--- a/src/dsql/Parser.cpp
+++ b/src/dsql/Parser.cpp
@@ -861,7 +861,7 @@ int Parser::yylexAux()
 			++charlen;			// Okay, just count 'em
 			++lex.ptr;			// and advance...
 
-			if (charlen > 16)	// Too many digits...
+			if (charlen > 32)	// Too many digits...
 			{
 				hexerror = true;
 				break;
@@ -872,11 +872,24 @@ int Parser::yylexAux()
 		// an NUMBER32BIT or NUMBER64BIT.
 		if (!hexerror)
 		{
+			if (charlen > 16)
+			{
+				// we deal with int128
+				fb_assert(charlen <= 32);	// charlen is always <= 32, see 10-15 lines upper
+
+				Firebird::string sbuff(hexstring, charlen);
+				sbuff.insert(0, "0X");
+
+				yylval.lim64ptr = newLim64String(sbuff, 0);
+
+				return TOK_NUM128;
+			}
+
 			// if charlen > 8 (something like FFFF FFFF 0, w/o the spaces)
 			// then we have to return a NUMBER64BIT. We'll make a string
 			// node here, and let make.cpp worry about converting the
 			// string to a number and building the node later.
-			if (charlen > 8)
+			else if (charlen > 8)
 			{
 				char cbuff[32];
 				fb_assert(charlen <= 16);	// charlen is always <= 16, see 10-15 lines upper
diff --git a/src/jrd/cvt.cpp b/src/jrd/cvt.cpp
index 7eb84425471..04244909689 100644
--- a/src/jrd/cvt.cpp
+++ b/src/jrd/cvt.cpp
@@ -218,6 +218,13 @@ UCHAR CVT_get_numeric(const UCHAR* string, const USHORT length, SSHORT* scale, v
 	bool digit_seen = false, fraction = false, over = false;
 
 	const UCHAR* p = string;
+	if (p[0] == '0' && p[1] == 'X')
+	{
+		*(Int128*) ptr = CVT_hex_to_int128(reinterpret_cast<const char*>(p + 2), length - 2);
+		*scale = 0;
+		return dtype_int128;
+	}
+
 	const UCHAR* const end = p + length;
 	for (; p < end; p++)
 	{