If I remember well, it was libspeex1, but I do not remember the version that it was installed before. Now I have installed libspeex1 1.2~rc1-1maemo7+0m5. And curiously it seems a dependency of Mirror app (trying to uninstall Mirror says that libspeex1 will also be uninstalled), although I cannot find this dependency in the web of Mirror: http://maemo.org/packages/package_in.../mirror/2.1-1/

Does this help you?