R Build won't find correct version of package -

i have 2 locations r-packages on server.

> .libpaths() [1] "/home/jakobr/.r/library"     "/opt/r/r-3.1.2/lib/r/library" 

i set .libpaths() in ~/.rprofile , works fine. when use attachnamespace(pckgb) or library(pckgb), sessioninfo() tells me have version want. in /opt/r/r-3.1.2/lib/r/library there outdated version of pckgb when want build pckga needs updated version of pckgb tells me

*** moving datasets lazyload db ** inst ** byte-compile , prepare package lazy loading error in loadnamespace(i, c(lib.loc, .libpaths()), versioncheck = vi[[i]]) :    namespace ‘pckgb’ 1.5.1 loaded, >= 1.6.0 required error: lazy loading failed package ‘pckga’ 

how can r ignore directory /opt/r/r-3.1.2/lib/r/library don't have writing access to.