Problems in Replacing libc.so.6

[Suma]

I have download the glibc-2.2.93 sources. Built the libs(interested in
libc.a). I have to add an extra ".o" file to this archive. To include
the functionality in libc.a that I intend. 
After I added the .o to the libc.a archive. I ran the make install of
glibc-2.2.93 to build the respective shared object files for libc.a.
This was done in custom folder that was defined during configuration and
hence the orginal lib and the shared object files in /usr/lib or /lib
remained intact.

Now the problem is libc.so.6 is present both in /lib and /lib/i686
When i tried to relace the libc.so.6 in /lib. The functionality that i
added to the libc did'nt seem to be happening.However the libc.a shows
my object file when i do "nm" on the libc.a.

Then when i did a "ldd" on the executable that i had built(say a sample
server program).The output of that looked like this

libc.so.6 => /lib/i686/libc.so.6 (0x42000000)
libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x40027000)
libm.so.6 => /lib/i686/libm.so.6 (0x400d9000)
libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x400fb000)
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)

So I thought the actual libc.so.6 which the program default picks up was
from /lib/i686/libc.so.6 folder. Finally when I tried to replace this
libc.so.6, that was the last thing that happened on my system. System
crashed and then "/" partition was completely corrupted. Offcourse then
the linux had to be installed again.

Now i am in real fix, Can we ever replace the libc.so.6. If so from
where and how(without another crash).

Thanxs for the patience
Cheers
Suma