[R-br] Pacote rJava

Olá!
Estou com dificuldade para carregar o pacote rJava. Por favor, alguém 
poderia me ajudar?
Vejam as mensagens:

 > utils:::menuInstallPkgs()
--- Please select a CRAN mirror for use in this session ---
trying URL 
'http://www.vps.fmvz.usp.br/CRAN/bin/windows/contrib/3.0/rJava_0.9-6.zip'
Content type 'application/zip' length 758820 bytes (741 Kb)
opened URL
downloaded 741 Kb

package ‘rJava’ successfully unpacked and MD5 sums checked

The downloaded binary packages are in
C:\Users\Unesp\AppData\Local\Temp\Rtmpsx6PLo\downloaded_packages
 > local({pkg <- select.list(sort(.packages(all.available = 
TRUE)),graphics=TRUE)
+ if(nchar(pkg)) library(pkg, character.only=TRUE)})
Error : .onLoad failed in loadNamespace() for 'rJava', details:
   call: fun(libname, pkgname)
   error: JAVA_HOME cannot be determined from the Registry
Error: package or namespace load failed for ‘rJava’




-- 
Gislaine Cristina Batistela