Inconsistency on Hexadecimal numbers - BASE produces Hexadecimal with uppercase only, HEX2DEC "must accept lowercase"

Change 5.19.1 to read: 5.19.1 General These functions convert between different representations of numbers, such as between different bases and Roman numerals. The base conversion functions xxx2BIN (such as DEC2BIN), xxx2OCT, and xxx2HEX functions return text, while the xxx2DEC functions return Number. All of the xxx2yyy functions accept either text or number; a number is interpreted as the strring of digits when represented in base 10. These functions are intended to support relatively small numbers, and have a somewhat convoluted interface and semantics, as described in their specifications. General base conversion capabilities are provided by BASE and DECIMAL, which are recommended instead. As an argument for the HEX2xxx functions, a hexadecimal number is any string consisting solely of the characters "0","1" to "9", "a" to "f" and "A" to "F". The hexadecimal output of an xxx2HEX function shall be a string consisting solely of the characters "0","1" to "9" (U+0030 through U+0039), "a" to "f" (U+0061 through U+0066) and "A" to "F" (U+0041 through U+0046), and should be a string consisting solely of the characters "0","1" to "9" and "A" to "F". In both cases, the 40th bit (from the right) is considered a sign bit. Moreover add, to the constraints of the HEX2xxx functions: X is a hexadecimal number as described in 5.19.1.