if (document.images) {
main_index_b1_off   = new Image(); main_index_b1_off.src   = "images/navbar/main_index_b1.gif"
main_index_b1_over  = new Image(); main_index_b1_over.src  = "images/navbar/main_index_b1_over.gif"
main_index_b2_off   = new Image(); main_index_b2_off.src   = "images/navbar/main_index_b2.gif"
main_index_b2_over  = new Image(); main_index_b2_over.src  = "images/navbar/main_index_b2_over.gif"
main_index_b3_off   = new Image(); main_index_b3_off.src   = "images/navbar/main_index_b3.gif"
main_index_b3_over  = new Image(); main_index_b3_over.src  = "images/navbar/main_index_b3_over.gif"
main_index_b4_off   = new Image(); main_index_b4_off.src   = "images/navbar/main_index_b4.gif"
main_index_b4_over  = new Image(); main_index_b4_over.src  = "images/navbar/main_index_b4_over.gif"
main_index_b5_off   = new Image(); main_index_b5_off.src   = "images/navbar/main_index_b5.gif"
main_index_b5_over  = new Image(); main_index_b5_over.src  = "images/navbar/main_index_b5_over.gif"
main_index_b6_off   = new Image(); main_index_b6_off.src   = "images/navbar/main_index_b6.gif"
main_index_b6_over  = new Image(); main_index_b6_over.src  = "images/navbar/main_index_b6_over.gif"
main_index_b7_off   = new Image(); main_index_b7_off.src   = "images/navbar/main_index_b7.gif"
main_index_b7_over  = new Image(); main_index_b7_over.src  = "images/navbar/main_index_b7_over.gif"
main_index_b8_off   = new Image(); main_index_b8_off.src   = "images/navbar/main_index_b8.gif"
main_index_b8_over  = new Image(); main_index_b8_over.src  = "images/navbar/main_index_b8_over.gif"
main_index_b9_off   = new Image(); main_index_b9_off.src   = "images/navbar/main_index_b9.gif"
main_index_b9_over  = new Image(); main_index_b9_over.src  = "images/navbar/main_index_b9_over.gif"
main_index_b10_off  = new Image(); main_index_b10_off.src  = "images/navbar/main_index_b10.gif"
main_index_b10_over = new Image(); main_index_b10_over.src = "images/navbar/main_index_b10_over.gif"
main_index_b11_off  = new Image(); main_index_b11_off.src  = "images/navbar/main_index_b11.gif"
main_index_b11_over = new Image(); main_index_b11_over.src = "images/navbar/main_index_b11_over.gif"
main_index_b12_off  = new Image(); main_index_b12_off.src  = "images/navbar/main_index_b12.gif"
main_index_b12_over = new Image(); main_index_b12_over.src = "images/navbar/main_index_b12_over.gif"
main_index_b13_off  = new Image(); main_index_b13_off.src  = "images/navbar/main_index_b13.gif"
main_index_b13_over = new Image(); main_index_b13_over.src = "images/navbar/main_index_b13_over.gif"
main_index_b14_off  = new Image(); main_index_b14_off.src  = "images/navbar/main_index_b14.gif"
main_index_b14_over = new Image(); main_index_b14_over.src = "images/navbar/main_index_b14_over.gif"
main_index_b15_off  = new Image(); main_index_b15_off.src  = "images/navbar/main_index_b15.gif"
main_index_b15_over = new Image(); main_index_b15_over.src = "images/navbar/main_index_b15_over.gif"

reps_b1_off         = new Image(); reps_b1_off.src         = "images/navbar/reps_b1.gif"
reps_b1_over        = new Image(); reps_b1_over.src        = "images/navbar/reps_b1_over.gif"

learn_b1_off         = new Image(); learn_b1_off.src       = "images/navbar/learn_b1.gif"
learn_b1_over        = new Image(); learn_b1_over.src      = "images/navbar/learn_b1_over.gif"
}

function turn_off(ImageName) {
	if (document.images != null) {
		document[ImageName].src = eval(ImageName + "_off.src");
	}
}

function turn_over(ImageName) {
	if (document.images != null) {
		document[ImageName].src = eval(ImageName + "_over.src");
	}
}