diff --git a/gnu/packages/mail.scm b/gnu/packages/mail.scm
index f78fe0a769..481775e362 100644
--- a/gnu/packages/mail.scm
+++ b/gnu/packages/mail.scm
@@ -2112,6 +2112,8 @@ delivery.")
                        (("(ZCAT_COMMAND=).*" all var)
                         (string-append var (search-input-file inputs "bin/zcat")
                                        "\n"))
+                       (("# (SUPPORT_SOCKS=yes)" all line) line)
+                       (("# (SUPPORT_PROXY=yes)" all line) line)
                        (("# (USE_GNUTLS(|_PC)=.*)" all line)
                         (string-append line "\n"))
                        (("# (AUTH_CRAM_MD5=yes)" all line) line)