diff -up ./cmd/selfserv/selfserv.c.ipv6_fix ./cmd/selfserv/selfserv.c
--- ./cmd/selfserv/selfserv.c.ipv6_fix	2021-09-14 11:40:06.176408531 -0700
+++ ./cmd/selfserv/selfserv.c	2021-09-14 11:49:46.361907308 -0700
@@ -1717,14 +1717,28 @@ getBoundListenSocket(unsigned short port
     PRNetAddr addr;
     PRSocketOptionData opt;
 
-    addr.inet.family = PR_AF_INET;
-    addr.inet.ip = PR_INADDR_ANY;
-    addr.inet.port = PR_htons(port);
+    if (PR_SetNetAddr(PR_IpAddrAny, PR_AF_INET6, port, &addr) != PR_SUCCESS) {
+	errExit("PR_SetNetAddr");
+    }
 
-    listen_sock = PR_NewTCPSocket();
+    listen_sock = PR_OpenTCPSocket(PR_AF_INET6);
     if (listen_sock == NULL) {
         errExit("PR_NewTCPSocket");
     }
+    /* NSPR has a bug where set inheritable doesn't work unless it's a pure
+     * NSPR socket. If we have an IPV6 emulator on an IPV4 socket, it will fail.
+     * In that case just open an IPV4 socket instead */
+    if (PR_NSPR_IO_LAYER !=  PR_GetLayersIdentity(listen_sock)) {
+        PR_Close(listen_sock);
+        addr.inet.family = PR_AF_INET;
+        addr.inet.ip = PR_INADDR_ANY;
+        addr.inet.port = PR_htons(port);
+
+        listen_sock = PR_NewTCPSocket();
+        if (listen_sock == NULL) {
+            errExit("PR_NewTCPSocket");
+        }
+    }
 
     opt.option = PR_SockOpt_Nonblocking;
     opt.value.non_blocking = PR_FALSE;