Problem when compiling CBUF.LIB

Hi to all.
I am using DC 9,50. For my project I use RS232 library together with CBUF.LIB. But, I am getting error when compiling:
Unexpected token in instruction : " >>> 0 <<< HL, DE", expected one of { mnemonic, ‘,’, end-of-line }.
This is the code with bolded lin where error is:
/*** Beginheader cbuf_used /
int cbuf_used (char buf);
/
* endheader */

/* _START FUNCTION DESCRIPTION ********************************************
cbuf_used

SYNTAX: int cbuf_used(char *circularBuffer);

DESCRIPTION: Calculates used up data space, (back-front+mask+1)&mask.

PARAMETER1: circularBuffer: Circular buffer.

RETURN VALUE: None
END DESCRIPTION **********************************************************/

#asm xmem

cbuf_used::
PUSH IX
LD IX,(SP+RETADDRESS_SIZE+2)
LD HL,(IX+2)
LD C,L
LD B,H
LD HL,(IX+6)
EX DE,HL
LD HL,(IX+4)
OR A ; clear carry
SBC HL,BC ; (front-back+mask)&mask
ADD HL,DE ;
INC HL
AND HL,DE
POP IX
LRET

#endasm

Can you please help me solve this? BTW, file CBUF.LIB is part of DC 9.50 installation.
Thank you,
Sandi