I've found this J fare All in on ITA but I can't book it :

Fare (A1): TK ISTCPT JPRM8D fare (rules) €166.50
Fare (A2): TK CPTIST JPRM8D fare (rules) €166.50
Tax: Turkish Int'l Airport Service Charge €5.00
Tax: Turkish Int'l Airport Service Charge $15.00
Tax: South Africa Air Passenger Tax ZAR 120
Tax: TK YR surcharge €180.00
Tax: South Africa Passenger Service Charge ZAR 224
Tax: South Africa Passenger Safety Charge ZAR 30
Total for 1 adult passenger: TRY 1057.84

(as of Saturday, June 21, 2008 5:29pm; fares loaded Saturday, June 21, 2008 5:00am)
Fare construction (sometimes useful to travel agents):
IST TK CPT 254.69JPRM8D TK IST 254.69JPRM8D NUC 509.38 END ROE 0.653715 FARE EUR 333.00 EQU TRY 632.00 XT 27.84TR 4.56EV 18.15WC 33.89ZA 341.40YR