[R] Apparent problem with \eqn

[Ross Boylan]

  \eqn{{\bf\beta}_j}{b(j)} in my .Rd file produces this error
--------------------------------------------
! Missing $ inserted.
<inserted text> 
                $
l.7 \eqn{{\bf\beta}_j}{\bf\beta}_
                                 jnormal-bracket5bracket-normal{b(j)}
--
! Missing $ inserted.
<inserted text> 
                $
l.16 
     
--
! Missing } inserted.
<inserted text> 
                }
l.16 
     
--
! Extra }, or forgotten \endgroup.
\par ...m \@noitemerr {\@@par }\fi \else {\@@par }
                                                  \fi 
l.16 
-------------------------------
Is this a bug, or am I missing something?  Note that \bf\beta seems to
have been doubled.

Currently on R 2.2.0.final-4 on Debian.  I think I've seen this with
many prior versions too.
     
-- 
Ross Boylan                                      wk:  (415) 514-8146
185 Berry St #5700                               ross at biostat.ucsf.edu
Dept of Epidemiology and Biostatistics           fax: (415) 514-8150
University of California, San Francisco
San Francisco, CA 94107-1739                     hm:  (415) 550-1062