diff --git a/bswap.h b/bswap.h
index 970c1bb..523d805 100644
--- a/bswap.h
+++ b/bswap.h
@@ -132,6 +132,7 @@
 #define cpu_to_le32wu(p, v) cpu_to_le32w(p, v)
 #define le16_to_cpupu(p) le16_to_cpup(p)
 #define le32_to_cpupu(p) le32_to_cpup(p)
+#define be32_to_cpupu(p) be32_to_cpup(p)
 
 #define cpu_to_be16wu(p, v) cpu_to_be16w(p, v)
 #define cpu_to_be32wu(p, v) cpu_to_be32w(p, v)
@@ -168,6 +169,12 @@
     return p1[0] | (p1[1] << 8) | (p1[2] << 16) | (p1[3] << 24);
 }
 
+static inline uint32_t be32_to_cpupu(const uint32_t *p)
+{
+    const uint8_t *p1 = (const uint8_t *)p;
+    return p1[3] | (p1[2] << 8) | (p1[1] << 16) | (p1[0] << 24);
+}
+
 static inline void cpu_to_be16wu(uint16_t *p, uint16_t v)
 {
     uint8_t *p1 = (uint8_t *)p;
diff --git a/hw/e1000.c b/hw/e1000.c
index 6e22ef9..8756d3b 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -326,7 +326,7 @@
         if (tp->tcp) {
             sofar = frames * tp->mss;
             cpu_to_be32wu((uint32_t *)(tp->data+css+4),	// seq
-                be32_to_cpup((uint32_t *)(tp->data+css+4))+sofar);
+                be32_to_cpupu((uint32_t *)(tp->data+css+4))+sofar);
             if (tp->paylen - sofar > tp->mss)
                 tp->data[css + 13] &= ~9;		// PSH, FIN
         } else	// UDP