diff --git a/src/ngircd/conn.c b/src/ngircd/conn.c
index e92240b6..e58e6335 100644
--- a/src/ngircd/conn.c
+++ b/src/ngircd/conn.c
@@ -858,7 +858,7 @@ static bool
 Conn_Write( CONN_ID Idx, char *Data, size_t Len )
 {
 	CLIENT *c;
-	size_t writebuf_limit = WRITEBUFFER_LEN;
+	size_t writebuf_limit = WRITEBUFFER_MAX_LEN;
 	assert( Idx > NONE );
 	assert( Data != NULL );
 	assert( Len > 0 );
@@ -894,7 +894,7 @@ Conn_Write( CONN_ID Idx, char *Data, size_t Len )
 		/* Uncompressed link:
 		 * Check if outbound buffer has enough space for the data. */
 		if (array_bytes(&My_Connections[Idx].wbuf) + Len >=
-		    writebuf_limit) {
+		    WRITEBUFFER_FLUSH_LEN) {
 			/* Buffer is full, flush it. Handle_Write deals with
 			 * low-level errors, if any. */
 			if (!Handle_Write(Idx))
diff --git a/src/ngircd/defines.h b/src/ngircd/defines.h
index 3f1122ca..ec7bee93 100644
--- a/src/ngircd/defines.h
+++ b/src/ngircd/defines.h
@@ -59,9 +59,12 @@
 
 #define READBUFFER_LEN 2048		/* Size of the read buffer of a
 					   connection in bytes. */
-#define WRITEBUFFER_LEN 4096		/* Size of the write buffer of a
+#define WRITEBUFFER_FLUSH_LEN 4096	/* Size of a write buffer that triggers
+					   buffer flushing if more space is
+					   needed for storing data. */
+#define WRITEBUFFER_MAX_LEN 32768	/* Maximum size of the write buffer of a
 					   connection in bytes. */
-#define WRITEBUFFER_SLINK_LEN 51200	/* Size of the write buffer of a
+#define WRITEBUFFER_SLINK_LEN 65536	/* Maximum size of the write buffer of a
 					   server link connection in bytes. */
 
 #define PROTOVER "0210"			/* Implemented IRC protocol version,