Incompatibility error - 64bits

Im trying to install nagios in a 64bits machine but i get this error with all the .o files and cant finish instalation… Is there any way to fix or avoid this?

/usr/bin/ld: warning: i386 architecture of input file comments-cgi.o' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input filexcomments-cgi.o’ is incompatible with i386:x86-64 output