Index: /trunk/src/VBox/Devices/Network/slirp/ip_icmp.c
===================================================================
--- /trunk/src/VBox/Devices/Network/slirp/ip_icmp.c	(revision 22896)
+++ /trunk/src/VBox/Devices/Network/slirp/ip_icmp.c	(revision 22897)
@@ -487,8 +487,14 @@
     register struct icmp *icp;
     register struct mbuf *m;
+#ifdef VBOX_WITH_SLIRP_BSD_MBUF
+    uint8_t *buf; /*(vvl) probably should be used mbuf of corresponded size instead*/
+#endif
 
     DEBUG_CALL("icmp_error");
     DEBUG_ARG("msrc = %lx", (long )msrc);
     DEBUG_ARG("msrc_len = %d", msrc ? msrc->m_len : 0);
+#ifdef VBOX_WITH_SLIRP_BSD_MBUF
+    M_ASSERTPKTHDR(msrc);
+#endif
 
     if (type!=ICMP_UNREACH && type!=ICMP_TIMXCEED)
@@ -524,4 +530,5 @@
     }
 
+#ifndef VBOX_WITH_SLIRP_BSD_MBUF
     /* make a copy */
     if (!(m = m_get(pData)))
@@ -537,4 +544,14 @@
     memcpy(m->m_data, msrc->m_data, msrc->m_len);
     m->m_len = msrc->m_len;                /* copy msrc to m */
+#else
+    if (!(m = m_gethdr(pData, M_DONTWAIT, MT_HEADER)))
+        goto end_error;                    /* get mbuf */
+    if (m_append(pData, m, m_length(msrc, NULL), mtod(msrc, const char *)) == 0)
+    {
+        m_freem(pData, m);
+        goto end_error;
+    }
+    m->m_pkthdr.header = mtod(m, void *);
+#endif
 
     /* make the header of the reply packet */
@@ -543,6 +560,10 @@
 
     /* fill in icmp */
+#ifndef VBOX_WITH_SLIRP_BSD_MBUF
     m->m_data += hlen;
     m->m_len  -= hlen;
+#else
+    m_adj(m, hlen);
+#endif
 
     icp = mtod(m, struct icmp *);
@@ -553,5 +574,9 @@
         s_ip_len = ICMP_MAXDATALEN;
 
+#ifndef VBOX_WITH_SLIRP_BSD_MBUF
     m->m_len = ICMP_MINLEN + s_ip_len;     /* 8 bytes ICMP header */
+#else
+    m_adj(m, ICMP_MINLEN);
+#endif
 
     /* min. size = 8+sizeof(struct ip)+8 */
@@ -562,5 +587,17 @@
     icp->icmp_seq = 0;
 
+#ifndef VBOX_WITH_SLIRP_BSD_MBUF
     memcpy(&icp->icmp_ip, msrc->m_data, s_ip_len);   /* report the ip packet */
+#else
+    buf = RTMemAlloc(s_ip_len);
+    if (buf == NULL) 
+    {
+        m_free(pData, m);
+        LogRel(("NAT:ICMP: can't allocate intermediate buffer, icmp error wasn't sent\n"));
+        goto end_error;
+    }
+    m_copydata(msrc, 0, s_ip_len, buf);
+    m_append(pData, m, s_ip_len, buf); 
+#endif
     HTONS(icp->icmp_ip.ip_len);
     HTONS(icp->icmp_ip.ip_id);
@@ -577,6 +614,10 @@
             message_len = ICMP_MAXDATALEN;
         cpnt = (char *)m->m_data+m->m_len;
+#ifndef VBOX_WITH_SLIRP_BSD_MBUF
         memcpy(cpnt, message, message_len);
         m->m_len += message_len;
+#else
+        m_append(pData, m, message_len, message);
+#endif
     }
 #endif
@@ -585,6 +626,8 @@
     icp->icmp_cksum = cksum(m, m->m_len);
 
+#ifndef VBOX_WITH_SLIRP_BSD_MBUF
     m->m_data -= hlen;
     m->m_len += hlen;
+#endif
 
     /* fill in ip */