diff -ur gaim-0.77-orig/src/protocols/oscar/oscar.c gaim-0.77/src/protocols/oscar/oscar.c
--- gaim-0.77-orig/src/protocols/oscar/oscar.c	2004-04-22 04:53:15.000000000 +0300
+++ gaim-0.77/src/protocols/oscar/oscar.c	2004-05-22 15:50:29.000000000 +0300
@@ -410,6 +410,48 @@
 	return utf8;
 }
 
+int isUTF8(char *str, size_t len)
+{
+	size_t i=0,tomatch;
+
+	while (i<len)
+	{
+		tomatch=-2;
+		/* If starts with bit 0 */
+		if ((str[i]&0x80)==0x0) tomatch=0;
+		else
+      		/* if starts with 110, and next starts with 10 */
+       		if ((str[i]&0xe0)==0xc0) tomatch=1;
+       		else
+   		/* if starts with 1110 and next two start with 10 */
+      	        if ((str[i]&0xf0)==0xe0) tomatch=2;
+	       	else
+	        /* if starts with 11110.and next 3 start with 10 */
+		if ((str[i]&0xf8)==0xf0) tomatch=3;
+		else
+		/* if starts with 111110.and next 4 start with 10 */
+		if ((str[i]&0xfc)==0xf8) tomatch=4;
+		else
+		/* if starts with 1111110.and variable numer of next chars starts with 10 */
+		if ((str[i]&0xfe)==0xfc) tomatch=-1;
+
+		if (tomatch==-2) return 0;
+		if (tomatch==-1)
+			while ( (str[++i]&0xc0)==0x80 && (i<len) ) continue;
+		else
+			while (tomatch!=0 && i<len)
+			{
+				if ((str[++i]&0xc0)!=0x80) return 0;
+				tomatch--;
+			}
+		i++;
+	}
+
+	return 1;
+
+
+}
+
 static char *oscar_caps_to_string(guint caps)
 {
 	static char buf[512], *tmp;
@@ -2545,12 +2587,18 @@
 		if (!args->msg || !args->msglen)
 			return 1;
 
-		tmp = g_convert(args->msg, args->msglen, "UTF-8", "ISO-8859-1", NULL, &convlen, &err);
-		if (err) {
-			gaim_debug_info("oscar",
-					   "ISO-8859-1 IM conversion: %s\n", err->message);
-			tmp = g_strdup(_("(There was an error receiving this message)"));
-			g_error_free(err);
+		if (isUTF8(args->msg, args->msglen)==0) {
+			tmp = g_convert(args->msg, args->msglen, "UTF-8", "CP1251", NULL, &convlen, &err);
+			if (err) {
+				gaim_debug_info("oscar",
+						   "ISO-8859-1 IM conversion: %s\n", err->message);
+				tmp = g_strdup(_("(There was an error receiving this message)"));
+				g_error_free(err);
+			}
+		}
+		else
+		{
+			tmp=g_strdup(args->msg);
 		}
 	}
 
@@ -2872,12 +2920,14 @@
 	msg2 = (gchar **)g_malloc((numtoks+1)*sizeof(gchar *));
 	for (i=0; msg1[i]; i++) {
 		gaim_str_strip_cr(msg1[i]);
-		msg2[i] = g_convert(msg1[i], strlen(msg1[i]), "UTF-8", "ISO-8859-1", NULL, NULL, &err);
-		if (err) {
-			gaim_debug_error("oscar",
-					   "Error converting a string from ISO-8859-1 to "
-					   "UTF-8 in oscar ICBM channel 4 parsing\n");
-			g_error_free(err);
+		if ( isUTF8(msg1[i],strlen(msg1[i]))!=0 ) {
+			msg2[i] = g_convert(msg1[i], strlen(msg1[i]), "UTF-8", "CP1251", NULL, NULL, &err);
+			if (err) {
+				gaim_debug_error("oscar",
+						     "Error converting a string from ISO-8859-1 to "
+						     "UTF-8 in oscar ICBM channel 4 parsing\n");
+				g_error_free(err);
+			}
 		}
 	}
 	msg2[i] = NULL;