private List<String> getNumCombinations(String phoneNum) {

		List<String> numCombinations = new ArrayList<String>();

		// Get Position Combinations for Inserting, each combination may form a new set of words
		List<String> insertPointList = getInsertPositions(phoneNum.length() - 1);
		Iterator<String> itorator = insertPointList.iterator();
		while (itorator.hasNext()) {
			String insertPointStr = itorator.next();
			
			//char[] insertPoints = insertPointStr.toCharArray();
			String[] insertPoints = insertPointStr.split(DELIMITER_POS);

			StringBuilder sb = new StringBuilder();
			String substr = "";
			int lastposition = 0;
			for (int i = 0; i < insertPoints.length; i++) {
				int position = Integer.parseInt(insertPoints[i]);

				substr = phoneNum.substring(lastposition, position);
				if (!"".equals(substr)) {
					sb.append(substr + DELIMITER);
				}

				lastposition = position;
			}
			// Add last part
			sb.append(phoneNum.substring(lastposition));

			numCombinations.add(sb.toString());
		}

		return numCombinations;

	}