To replace the standard terminal colours by those used e.g. in Gnome-Terminal:
# ~/.mrxvtrc Mrxvt.color0: #2E3436 Mrxvt.color1: #CC0000 Mrxvt.color2: #4E9A06 Mrxvt.color3: #C4A000 Mrxvt.color4: #3465A4 Mrxvt.color5: #75507B Mrxvt.color6: #06989A Mrxvt.color7: #D3D7CF Mrxvt.color8: #555753 Mrxvt.color9: #EF2929 Mrxvt.color10: #8AE234 Mrxvt.color11: #FCE94F Mrxvt.color12: #729FCF Mrxvt.color13: #AD7FA8 Mrxvt.color14: #34E2E2 Mrxvt.color15: #EEEEEC