invalid \uxxxx sequence while trying to create a package

I'm running R2.6.2 on a DELL box with 2gig RAM, using Rtools (v26).

I have a perplexing problem trying to build a package.  

I've created a small demonstration:

problem.demo  <- function () 
{cat("\n          ***   \u00e2 vs a    ***\n")}


This function runs in an R gui session and Rtools makes a simple package
containing it alone or with a handful of similar routines.

However, when I include it with a much bigger package (that Rtools has no
trouble in packaging without it), the result is an invalid \uxxxx sequence:

Compile time: 0 minutes, 3 seconds
171     Topics
342     Local links
171     Internet links
1       Graphic


Created
c:\DOCUME~1\CHARLE~1\LOCALS~1\Temp\Rbuild406495938\mh1823\chm\mh1823.chm,
149,803 bytes
Compression decreased file by 398,668 bytes.
  preparing package mh1823 for lazy loading
Loading required package: rcom
Loading required package: RODBC
Loading required package: RColorBrewer
Loading required package: survival
Loading required package: splines
Error in parse(n = -1, file = file) : invalid \uxxxx sequence
Calls: <Anonymous> -> code2LazyLoadDB -> sys.source -> parse
Execution halted
make: *** [lazyload] Error 1
*** Installation of mh1823 failed ***

Removing 'C:/DOCUME~1/CHARLE~1/LOCALS~1/Temp/Rinst406445831/mh1823'

Clearly I am overlooking something obvious, so I would greatly appreciate
any guidance.