Things I cant understand

[Joao Daniel]

Folks,

I'm trying to install Snort. So, the first step is update libpcap. Look 
what I have done.
1)

yum erase libpcap (to unistall old libpcap)
tar -zxfv libpcap
cd libpcap
./configure --libdir=/lib/ --bindir=/bin/
make
make install

2)

yum install ./daq.rpm

At this point I got a messagen telling that libpcap is not installed!!!

What is happening ? Did I made a mistake? Better: Why yum cant realize 
that lipcap is already installed ?