I've see this kind of error before. That lib has another lib linked to it which cannot be found.
You can view all the libs which are required for this lib to work by doing this
ldd /usr/local/lib/libmyodbc3-3.51.27.so
In this case you'll want to run
ldd /usr/local/lib/libmyodbc3-3.51.27.so | grep -i odbc
This will show you that libmyodbc3-3.51.27.so requires libodbc.so.1
Now, libodbc.so.1 is part of unixODBC-2.3.0 but CentOS comes with unixODBC-2.2.14 which has libodbc.so.2
You'll need to create a symbolic link from libodbc.so.1 to libodbc.so.2 and that shod fix the problem.