For SLE 10 SP4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/zypp:zc10/SLE_10_SP4/zypp:zc10.repo
zypper refresh
zypper install zypper
For SLE 10 SP3 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/zypp:zc10/SLE_10_SP3/zypp:zc10.repo
zypper refresh
zypper install zypper
For SLE 10 SP2 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/zypp:zc10/SLE_10_SP2/zypp:zc10.repo
zypper refresh
zypper install zypper