Using nautilus 3.4 on Ubuntu precise we had some wrapping issues in the icon view which turned out to be due to nautilus hacks to insert "zero width space" in labels to help wrapping at the right place

The specific bug we had is that "Install Ubuntu 12.04" would wrap after the point and show
"Install Ubuntu 12.
04"

the code is nautilus-icon-canvas-item.c

#define ZERO_WIDTH_SPACE "\xE2\x80\x8B"

#define ZERO_OR_THREE_DIGITS(p) \
	(!g_ascii_isdigit (*p) || \
	 (g_ascii_isdigit (*(p+1)) && \
	  g_ascii_isdigit (*(p+2))))
...
create_label_layout (NautilusIconCanvasItem *item,

	if (text != NULL) {
		str = g_string_new (NULL);

		for (p = text; *p != '\0'; p++) {
			str = g_string_append_c (str, *p);

			if (*p == '_' || *p == '-' || (*p == '.' && ZERO_OR_THREE_DIGITS (p+1))) {
				/* Ensure that we allow to break after '_' or '.' characters,
				 * if they are not likely to be part of a version information, to
				 * not break wrapping of foobar-0.0.1.
				 * Wrap before IPs and long numbers, though. */
				str = g_string_append (str, ZERO_WIDTH_SPACE);
			}"


There is one "obvious" bug, the define "g_ascii_isdigit (*p)" should be "g_ascii_isdigit (*(p))" instead

the current way ZERO_OR_THREE_DIGITS (p+1) has (*p) become (*p+1), or you want (*(p+1)) there

Fixing that issue resolve the initial bug I described.

Still the ZERO_OR_THREE_DIGITS() hack feels wrong, nothing tell you that IPs will have 3 digits or that version numbers follow the described scheme

I would suggesting drop the define and replace the code this way

-			if (*p == '_' || *p == '-' || (*p == '.' && ZERO_OR_THREE_DIGITS (p+1))) {
+			if (*p == '_' || *p == '-' || (*p == '.' && !g_ascii_isdigit(*(p+1)))) {

if you want to keep the current logic to "help" wrapping