This release addresses a number of correctness and reliability problems with the ptrace backend. Tavis Ormandy provided fixes for the following problems: a potential escape of socket aliases and double free and a problem with fork and ptrace (CVE-2007-4773). The tar ball for Systrace 1.6e can be downloaded here. Just keep in mind that ptrace has not been designed as a security primitive and while the ptrace backend can restrict the behavior of programs in non-adversarial settings, there are many ways to circumvent it.