[R] RODBC fails to build

[Vittorio]

Context:Pentium 4, FreeBSD 5.4, R 2.2.0

I updated the extra packages I 
had downloaded but the upgrading of RODBC failed complaining:

checking 
for unistd.h... yes
checking sql.h usability... no
checking sql.h 
presence... no
checking for sql.h... no
checking sqlext.h usability... 
no
checking sqlext.h presence... no
checking for sqlext.h... no
configure: error: "ODBC headers sql.h and sqlext.h not found"
ERROR: 
configuration failed for package 'RODBC'

The two header files are 
present in my box under /usr/local/include; I tried to symlink them to 
/usr/include and to /usr/local/lib/R/include to no avail.

Please help.

Vittorio