The sp-freeze program

sp-freeze /package/admin/foo [/package ...]

sp-freeze looks under the specified category directories (defaulting to $SP_ROOT/package) to find packages that depend on the given package (/package/admin/foo) via symlinks in their conf/ or spf/ subdirectories. Any such dependencies found will be updated to point to the current "current version" (for example, /package/admin/foo-1.2.3), rather than point to the /package/admin/foo current-version symlink itself.

This is useful when you are upgrading /package/admin/foo to a new version which breaks backward compatibility: you can use sp-freeze before the upgrade to make sure other packages continue using the old version, then upgrade /package/admin/foo, then upgrade the dependent packages to new versions which work with the new version of /package/admin/foo. Of course, this only works if the dependent packages refer to /package/admin/foo via a symlink in a conf/ or spf/ subdirectory.