Errorbars and $string_with_wave_name

Hi

I try to use errorbars in a generic fitting function that calls waves using $string_with_wave_name such as

display $Y_Wave_name vs  $X_Wave_name

(this is working)
However if I try to use

Errorbars $Y_Wave_name, XY wave=($XErr_Wave_name,$XErr_Wave_name),wave=($YErr_Wave_name,$YErr_Wave_name)

i have an error message saying that the trace is not on the graph.

I suspect a bug since if I use the same syntax with one particular set of names for X,Y Xerr and Yerr waves, Errorbars works fine
This works in Igor Pro 6.32:

Function Test()
	Make /O /N=5 xWave=p, yWave=0
	Make /O /N=5 xErrWave=1, yErrWave=1
	
	String X_Wave_name = "xWave", Y_Wave_name="yWave"
	String XErr_Wave_name = "xErrWave", YErr_Wave_name="yErrWave"
	
	Display $Y_Wave_name vs $X_Wave_name
	Errorbars $Y_Wave_name, XY wave=($XErr_Wave_name,$XErr_Wave_name),wave=($YErr_Wave_name,$YErr_Wave_name)
End


If you can't solve the problem post a fully function example like the one above.