When i mailed adsense abt kontera reply is I'd like to confirm that AdSense publishers may display third party advertisements on sites and pages showing Google ads as long as the formatting or color scheme of these ads is sufficiently different from the layout of the Google ads. In other words, if you choose to place non-Google ads on the same site or page as Google ads, it should always be clear to the user that the ads are served by different advertising networks and that the non-Google ads have no association with Google. If the formats are naturally similar, we'd ask that you use different color schemes for the competing ads.
Google has no problem with kontera as it not similar to their program. Again you can see the above letter from Google (as usual they won't be straight forward 'Yes' or 'No') you can use different colors schemes, so there is no problem using adsense and kontera on the same page..