missing space in R version specifier makes PACKAGES file unreadable by install.packages()

Hi,

After updating to R-3.0 beta r62328, I get the following:

install.packages("Biobase", type="source", repos="http://george2/BBS/2.12/bioc")

Error in do.call(op, list(v_c, v_t[[op]])) :
  could not find function "R (>=2.15.1)"

The problem can be fixed by adding a space after >= in the offending
package's DESCRIPTION file and re-generating the PACKAGES file with
tools:::write_PACKAGES().

However, this worked OK in r62077. I'm not sure if >=2.15.1 (without
the space) is valid syntax, but I wonder if R can be a bit more
forgiving, as this issue derailed our daily builds.

sessionInfo()

R version 3.0.0 alpha (2013-03-18 r62312)
Platform: x86_64-apple-darwin10.8.0 (64-bit)

locale:
[1] C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base

loaded via a namespace (and not attached):
[1] tools_3.0.0


Thanks,
Dan