Okay I solved the problem all by myself.

For wscons:

in your kernel config:
options 	WSDISPLAY_DEFAULTSCREENS=2 # at the least 1
options 	WSCONS_SUPPORT_PCVTFONTS	# support PCVT fonts

in your /etc/wscons.conf
font	pcvt	-	8	pcvt	/usr/share/pcvt/fonts/vt220h.808
font	ibm	-	8	ibm	/usr/share/pcvt/fonts/vt220l.808

#screen	0	-	vt100
#screen	1	-	vt100
screen	3	80x50bf	vt100
screen	4	80x50bf	vt100

be SURE to put pcvt first.  If the ibm font is loaded first, you just get   
the top of the font and when booting, the wscons setup will complain   
about not being able to find proper font and give you 50 lines of half   
characters.(I'm not sure why the order is important?)

Use 80x50bf not 80x50 otherwise you get 50 lines of half characters.

You will notice that screen 1 & 2 are remarked out, these are the two   
screens defined in the kernel with WSDISPLAY_DEFAULTSCREENS=2.  If you   
unremark them, wscons will just complain that "device busy" for those two   
virtual terminals and do nothing to them.

e.g. 'screen	1	80x50bf	vt100' will remain 25 lines.

This is really important, in /etc/rc.conf:
wscons=YES

Hope this helps someone.

It wouldn't be a bad thing to have information on 50 line mode in the   
i386 how to.

For pcvt:

132 col:
printf "\033[?3h"
stty rows 25 cols 132

80 col:
printf "\033[?3l"
stty rows 25 cols 80

50 lines:
scon -s 50

Now after all of that, it seems that pcvt doesn't support much of   
anything anymore, at least as of 1.4.  I tried getting pcvt to set the   
console to 50 line, nothing.  The man says pcvt can support 28, 40, 48,   
and 50 lines mode on VGA cards.

If you run the VT animation demos in   
/usr/src/arch/i386/isa/pcvt/Utils/demo with playvt (compiled in the same   
dir with make) scons is a bit faster and smoother than pcvt.

jam

BTW: If you're now curious about the vt demos, playvt's syntax is:
./playvt -d <delay> -f <filename>
On my Celeron 300 I had to use a delay of 30000.