getting the wrong font in ti-troff

[Lee Moore]

I am having a problem with Typesetter Independent Troff.  It is set up
with a DESC file that describes 26 different fonts.  The problem comes
when I ask for font "B" and I get font "LB".  Looking at the intermediate
output of Troff, font "B" gets mapped into 18 which is the number for
"LB" rather than the correct number: 3.  When I ask for font 3 explicitly,
(like with a \f3) things work correctly.

Anybody have an clues?  Below is out DESC file:

# describe the 'newraven' press device
res 2540
hor 1
vert 1
unitwidth 5
paperwidth 21590
paperlength 27940
sizes  5 6 7 8 9 10 11 12 13 14 15 16 18 20 24 30 36 48 72 0
fonts 26  R I B X AR cR ER GR GI GB GX HR HI HB HX hR LR LB LO OE tR TR UR MR HP S
charset
 ff Fi Fl fi fl \- hy sl ua <- ap A: O: Ao a: o: ao u: c, um .. ri
 ga aa be ma ct po ps *! sc bu dg dd pp I! !! I? hc ud 14 12 *P is
 cs *S bc __ de if di an .= fm sr +- cm -+ tf a/ ci sq tr dm a+ a-
 ax ag ** rh lh bs bx <= != >= cf fa mo C# gr te sb !s ib sp !S ip
 cr nm !m es pt r2 R# ~~ bt cu lo == mu QE l< r> da -> al ~> co pd
 ~= io <> im :> h- || no mc st |- |= rg NE NW SW SE << >> ca -| 34
 r1 *A *B *C *D *E *F *G *Y *I *K *L *M *N *O *H *R *T *U *W *X *Q
 *Z *a *b *c *d *e *f *g *y *i ts *k *l *m *n *o *p *h *r *s *t *u
 *w *x *q *z ru ul br lt lb rt rb lk rk bv lf rf lc rc mi pl eq rn
 em or \| \^
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