Can't open serial line /dev/cuaa0: no such file or direcotry (2)

[Mike Adams]

To whom it may concern: I'm using a programme called tempcontrol from Greg Lehey on a Dell pentium running BSD 6. When I run the programme, I get the above error.  
ls /dev shows that there is no cuaa0, only cuad0.  I see that this was changed to standardize naming conventions.
I've tried sh makedev cuaa0, but get the errorCan't open makedev: no such file or directory. 

I should be most grateful if someone can get me over this problem

Thanks in anticipation,

Michael Adams